INDEX

Topics are arranged alphabetically in the INDEX.
Showing posts with label Derrida. Show all posts
Showing posts with label Derrida. Show all posts

Sunday, March 8, 2015

Pioneers of Logic


Alice C. Linsley


Ancient logic

Plato’s view of reality was based on his belief that pattern can be seen in the order of nature and that we recognize pattern because it reflects the pattern intuitively grasped by the soul or inner person. The observable patterns in nature include the binary sets uniformly applied in the logic of the ancient world.

In mathematical terms, a binary set would be 1a+1b = {1} (binary set) in which the two entities are not equal. An example is male + female = human, but the male is larger and stronger than the female. The paradoxical nature of this is evident. This paradox was rejected as logical by modern pioneers in logic who, like Frege, insisted that 1+1 = a set of 2 and 2 = 1+1, a set of equals.

The anthropologist Levi-Strauss has demonstrated how binary logic is reflected in the thought of primitive peoples, and Jacques Derrida has shown how binary thinking is inescapable even in modern logic. This is because in a binary set we have more than one thing. Through disclosure or deconstruction, we find there are sets within sets.

Derrida saw the middle as a function by which binary opposites acquire extended meaning as merisms and reversals. These thinkers discovered in analysis of primitive myths that there are some universal ideas related to the most fundamental of human experiences such as birth, the Sun, and nourishment. This suggests weakness in nominalism, the view that there are no universal essences; that no abstract entities, essences, classes, or propositions have real existence.


Syllogistic reasoning

Aristotle (384-322 BC) is often credited with being the "father" of logic. He taught his students syllogistic logic. A syllogism attempts inference of one proposition from two premises. Each premise has one term in common with the conclusion. If (1)A = B, and (2)B = C, then (3)A = C. A standard-form categorical syllogism meets the following four conditions:

  1. All three statements are categorical propositions.
  2. The two occurrences of each term are identical.
  3. Each term is used in the same sense throughout the argument.
  4. The major premise is listed first, the minor premise second, and the conclusion is last.

Aristotle also deserves credit for modal logic because his evaluation of involves concepts like possibility, necessity, belief and doubt. He also identified several common fallacies

Aristotle dealt with the logical constants and, or, if ... then ..., not, and some and all. This is referred to as Naïve Set Theory because it relies on natural language to describe sets and the words and, or, if ... then, not, for some, for every are not subject to rigorous definition. Syllogisms may be useful in training young minds to reason according to a pattern, but they do not lead to discovery of anything new.

Naive sets are common in informal logic, but the 19th and 20th centuries saw the rise and refinement of formal logic, initiated by John Stuart Mill (1806-1873) and the brilliant mathematician Gottlob Frege (1848–1925).


John Stuart Mill

Mill was a British empiricist who formulated five principles of inductive reasoning in his A System of Logic, Ratiocinative and Inductive (1843). These are 1 Direct method of agreement2 Method of difference3 Joint method of agreement and difference4 Method of residue and 5 Method of concomitant variations.

John Stuart Mill
As an empiricist, Mill insisted that there is no metaphysical necessity. All necessity is conveyed in language and a matter of propositions. The world we describe propositionally is the world of our ordinary experience and observation. The ontology of the world is reflected in the language we use. Knowing the meaning of terms enables us to evaluate the importance of propositions.


Mill's Nominalism

Mill believed that the early versions of nominalism held that "there is nothing general except names." He was mistaken in this, as anthropologists subsequently demonstrated.

The earliest nominalism, as reflected in ancient lexemes, involved general names and complex related experiences including attributes and related ideas. Lexemes are the basis for early scripts such as ThamudicA solar lexeme such as Y or T or O represented a deified or divinely appointed ruler, his territory, his people, and all his resources such as water and gold. The Horite rulers are identified with the solar symbol Y: Yaqtan, Yishmael, Yitzak, Yisbak, Yacob, Yosef, Yeshua, etc. Other ancient lexemes include V, W and X.

Mill was correct that names of entities (nouns) have levels of meaning, or connotative variables. He showed that names denote either individuals or the attributes of individuals. A general name - white, for example - connotes an attribute and denotes all individuals that have that attribute. White connotes the attribute whiteness, and denotes all things that have that attribute.

Mill explored the variability of names through analysis of syllogisms. Here is one he used to illustrate that there is a connection between attributes connoted by terms, but the attributes are logically independent.

Consider the syllogism:
Man is mortal.
Socrates is a man.
Ergo, Socrates is mortal.
In the syllogism "man" and "mortal" are attributes. Given Mill's claim that attributes are logically independent, the major premise - Man is mortal - adds nothing to the truth of the propositions concerning Socrates. What matters is the particulars - Socrates and the attributes man and mortal. In other words, deductive inference cannot advance knowledge. There is nothing new discovered by the syllogism.

George Boole
George Boole (1815-1864) was an English mathematician and philosopher who developed some of Leibniz's ideas about the relationship between mathematics and logic in his book The Mathematical Analysis of Logic (1847). His later work An Investigation of the Laws of Thought, on Which Are Founded the Mathematical Theories of Logic (1854) presents a more complete system of symbolic reasoning.

Boolean logic is easy to understand. Begin with the idea that some statement (P) is either true or false. (He applies the law of the excluded middle). Then other statements can be formed, which are true or false, by combining these initial statements together using the fundamental operators And, Or and Not.

Boole's syllogistic reasoning did not place importance on the existential question, as happened with Aristotle. For Aristotle any proposition involving unicorns or satyrs, for example, would render an argument invalid. In Boole's view, anything named in a proposition does not imply that it in fact exists.

Consider the difference in their views:

Aristotle
All men are humans.  This implies the existence of men.
No maple trees are oaks.  This implies the existence of maple trees.
All unicorns are grand creatures.  This does not imply the existence of unicorns.

Boole
All men are humans.  This does not imply the existence of men. (Heidegger would love this!)
No maple trees are oaks.  This does not imply the existence of maple trees.
All unicorns/satyrs are grand creatures.  This does not imply the existence of unicorns/satyrs.


Gottlob Frege

Gottlob Frege
Friedrich Ludwig Gottlob Frege is considered another founder of modern logic and the father of analytic philosophy. Frege's logic is now known as second-order logic.

His first major work was Begriffsschrift, published in 1879. In 1884, The Foundations of Arithmetic appeared, and this was followed by two volumes known by the German title Grundgesetze.

Frege's writings were largely ignored when first published, partly because the English philosophers were not capable of reading the original German. That would change with Bertrand Russell (1872–1970), whose knowledge of German made it possible for him to understand Frege and even to refute him.

Russell was introduced to the significance of Frege's work in logic through Giuseppe Peano (1858–1932), who he met at a conference in Paris in and both of whom saw the merit of his work.

In 1903, Russell wrote an appendix to The Principles of Mathematics in which he presented deficiencies in the assumptions that Frege made in Grundgesetze, which Russell recognized led to paradox or contradiction. Russell communicated this to Frege by letter and Frege's response was to accuse Russell of undermining the whole of mathematics.

Others influenced by Frege's work include Alfred North Whitehead (1861–1947), Ludwig Wittgenstein (1889–1951), Willard van Orman Quine (1908-2000), and the Logical Positivist Rudolf Carnap (1891–1970). In his Der logische Aufbau der Welt, Carnap attempted to apply the concepts of Principia Mathematica to his discourse about sense data, the external world and logic. Quine would go beyond the Vienna Circle’s position that philosophy is properly defined as the philosophic study of the language of science. Though Quine was not a scientist, he saw his philosophy as science.


Proper Names and Cognitive Value

Leibniz developed an approach to questions of necessity, possibility, contingency that served an important function within his metaphysics and epistemology. This is called modal metaphysics and it has important implications for logic. Carnap thought one could give a possible world semantics for the modalities of necessity and possibility by giving the valuation function a parameter that ranges over Leibniz's possible worlds. We will explore this under "Modal Logic."

Frege agreed with Leibniz that natural language is unsuited to formal logic. This led Frege to create a symbolic language in which logical relations and possible inferences would be clear and unambiguous.

Frege’s term for such a language -“Begriffsschrift” - may have been borrowed from a paper on Leibniz written by Adolf Trendelenburg, considered by Søren Kierkegaard "one of the most sober philosophical philologists I know."

Leibniz’s Problem: Why doesn’t ‘2+3 = 5’ reduce to ‘5 = 5’? Frege does not address this problem, but instead recasts it. Frege’s Puzzle is about the semantics of proper names.

(1) Hesperus is Hesperus. (Hesperus is a proper name for the planet Venus.)
(2) Hesperus is Phosphorus. (Phosphorus is a personification of the planet Venus.)

Each of these sentences is true. 'Hesperus' refers to the same object as 'Phosphorus' (the planet Venus). Nonetheless, (1) and (2), though synonymous, differ in what Frege called "cognitive value." Frege thus rejects John Stuart Mill's view that a proper name has no meaning above and beyond the object to which it refers. Frege develops this in his book Sense and Reference.

David Kaplan demonstrates how it is rationally possible to believe one while denying the other with this:


"I am David Kaplan", spoken by David Kaplan.
"He is David Kaplan", spoken by someone pointing at David Kaplan.
"David Kaplan is David Kaplan", spoken by anyone.

All express the same content and refer to the same individual. Yet each has a different cognitive value. Kaplan explains this by associating cognitive value with character rather than content, thus providing what seems a remedy to Frege's problem.


Frege's Concept-Writing

Frege's most famous work is Begriffsschrift (Concept-Writing: A Formal Language for Pure Thought Modeled on that of Arithmetic). It marked a turning point in logic. Here Frege demonstrates that true contents do not follow directly from other true contents. This requires a mediating system or what has come to be called axiomatic predicate logic. The book includes a rigorous treatment of functions and variables.

Frege declared nine of his propositions to be axioms, and justified them by arguing informally that, given their intended meanings, they express self-evident truths. In contemporary notation, these axioms are:

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 


Frege wanted to show that mathematics grows out of logic, and devised techniques that took him beyond syllogistic and propositional logic to symbolic or formal logic. He accomplished this through his invention of quantified variables, which solved the problem of multiple generality.

Frege's symbolic logic was able to move beyond the logical constants and, or, if ... then ..., not, and some and all to more complex inferences. He prepared the way for the analysis of logical concepts by  Bertrand Russell (theory of descriptions), Kurt Gödel's incompleteness theorems, and to Alfred Tarski's (1901–1983) theory of truth. All owe a great debt to Frege's work.

Other philosophers who have responded to Frege's work include Saul Kripe (Naming and Necessity, 1980), David KaplanRuth Barcan Marcus, and Hilary Putnam. (We will look closer at Kripe's contribution when we study Modal Logic.)


Frege's Intention

In his work Frege intended to set forth a system to isolate logical principles of inference. He perceived the need for this because he saw that only formalized logic could be applied to the sciences. No longer would an intuitive element be permitted as an assumption/premise. It would be isolated and represented separately as an axiom. The proof was to be logical and without gaps.

Frege was an important influence on Russell who influenced Quine. Russell's work inspired Quine to pursue logic. Quine wrote, “Russell’s name is inseparable from mathematical logic, which owes him much, and it was above all Russell that made that subject an inspiration to philosophers.” In 1962, Quine wrote to Russell that “Principia Mathematica was what, of all books, has influenced me the most.”

Wittgenstein also studied Frege's work and in 1911, he wrote to Frege concerning his solution to Russell’s paradox (see below). Frege invited him to Jena to discuss his views. The two engaged in a philosophical debate, and Wittgenstein reported that Frege “wiped the floor” with him. However, Frege was impressed with Wittgenstein and suggested that he study with Russell at Cambridge.


Russell's Paradox and Wittgenstein's solution

Russell's paradox Z = {x : x is not a member of x}

If Z is a member of Z how can it not be a member of Z?

Is Z a member of Z? If yes, then by the defining quality of Z, Z is not a member of itself. This forces us to declare that Z is not a member of Z. Then Z is not a member of itself and so, again by definition of Z, Z is a member of Z. What we have here is the following contradiction: Z is a member of Z if and only if Z is not a member of Z.

In 1923, Ludwig Wittgenstein proposed to "dispose" of Russell's paradox as follows:

The reason why a function cannot be its own argument is that the sign for a function already contains the prototype of its argument, and it cannot contain itself. For let us suppose that the function F(fx) could be its own argument: in that case there would be a proposition 'F(F(fx))', in which the outer function F and the inner function F must have different meanings, since the inner one has the form O(f(x)) and the outer one has the form Y(O(fx)). Only the letter 'F' is common to the two functions, but the letter by itself signifies nothing. This immediately becomes clear if instead of 'F(Fu)' we write '(do): F(Ou). Ou = Fu'. That disposes of Russell's paradox. (Tractatus Logico-Philosophicus, 3.333)


Monday, December 29, 2014

The Story of Ontology


“The real question is why is there “being”? The existence of existence is amazing, awesome.”
Gerald Schroeder



Alice C. Linsley

In our study of epistemology, we encountered philosophers who recognized the importance of the imagination:  Hume, Kant, Kierkegaard, even Berkeley. Imagination plays a key role in this story of ontology.

Imagine that you are a spider weaving a web. As a master web-weaver how much thought is directed toward the creation of the web? Is this "ready-at hand" labor, as Heidegger suggests? What role does consciousness play in your actions?

Do you perceive of the web as the entire universe? Probably not, since you fabricated the web in such as way that it extends through air/space, and you are aware that you didn't fabricate the air/space.

Your construction of the web is a matter of daily coping. It is essential to trap other beings: flies, gnats, etc. This means that you are conscious of other beings in your universe.  The web is the spider's way to acquire nourishment to sustain its life, but does it recognize the web as a bounded ontological context?

There is the reality that the web will be broken and must be repaired or rebuilt. Is the spider's web-weaving existence pitiful? Does the spider wonder about the futility of his daily existence?

Of course, spiders do not reason as humans, but this illustrates how humans think about our existence. We fabricate from what we have and we think we are creators. Why is that? We recognize the existence of other entities in our world, especially those upon which we depend. We understand that things break in our world and sometimes the very web of our existence crashes. We grasp intellectually that there are other universes, but we do not know them because they are beyond our bounded context, our consciousness. Often our routines of daily existence cause us to wonder if all this effort is worth it.

The philosophical study of theories of existence and being is called "ontology" and it is probably my favorite area of philosophical study. The term "ontology" is derived from two Greek words: onto (being) and logia (written or spoken discourse).

In this unit, we will look at the nature of being, becoming, and existence (even extinction). In other words, we will explore the web, the air, the relationship of the web and the air, and the relationship of the web in air to the larger universe called "reality." Because the whole story of reality is an impossible tale for humans in our bounded ontological context, we will have to narrow our exploration. We will not wander far from metaphysics. We will not discuss ontology related to aesthetics or to ethics, though ontology determines and informs views of beauty, goodness, fairness, etc.

I hope to tell the story of ontology by staying with concrete particulars like air, fire, water and earth. Let us consider an illustration that employs fire.

When you build a fire, do you believe you have created the element of fire or do you recognize that you have merely started a process? When you contain the fire so that it will not spread, do you also contain the products of the process you started, the smoke and chemical reactions? You are safe while the fire is contained in a small space, but at the same time, you are not safe if the smoke and fumes are contained in the same small space. Apparently, the value or benefit of something being contained (bounded) is relative.

If these illustrations that speak of air and fire remind you of the pre-Socratic debates about primal substance, your thinking is headed in the right direction! Why did Thales, Anaximander, Anaximenes not agree as to the substance that makes existence possible? Because each had to interpret their experiences, and no two humans can have exactly the same interpretation. The art and science of interpretation is called hermeneutics. Maybe ontology is simply hermeneutics, or maybe hermeneutics is ontology.

That is what Martin Heidegger (1889-1976) thought. He developed this in his book Ontology--The Hermeneutics of Facticity (1988). The book is a compilation of the lectures he delivered at the University of Freiburg during the summer of 1923. In these lectures, Heidegger reviewed and critically appropriated the hermeneutic tradition, beginning with Plato, Aristotle, Augustine and including the thought of Schleiermacher (1768-1834) and Dilthey (1833-1911). He attempted to reformulate the question of being on the basis of facticity and the everyday world (phenomena/phenomenology).

Heidegger explored the structures of human consciousness, the categories of experience of being, what he called "Dasein." He is one of the philosophers whose work we will investigate in this unit on ontology. Another is Jacques Derrida, an Arabic-speaking, North African Jew who explored the relationship between ontology and theology, calling this "ontotheology," a term he picked up from Immanuel Kant. Derrida's deconstruction employs interpretative principles that have the effect of restoring a more ancient Afro-Asiatic approach to meaning (binary oppositions). He identifies the importance of context and presence, and initiates a deeply ontological conversation. A fundamental assertion of deconstruction is that "there is no outside-text" (il n'y a pas de hors-texte). This oft-quoted phrase from Derrida's Grammatology means simply (or complexly) there is nothing outside of context.

As we came to recognize in our study of epistemology, there are limits to what humans can know. There are perplexing questions that philosophers have never resolved. These include the mind-body problem: how can that which is not extended act on the material world?; and the problem of induction: when is the evidence sufficient? We hit the same roadblock when we explore the central questions of ontology: What really is?; What constitutes being? Plato's Forms was an approach that sought a way around the roadblock. For Plato, the objects perceived as existing have a nature that is beyond what is perceived by the senses. Things are not what they seem to be because they are reflections of the true Forms.

And that takes us to our next illustration. This one uses the element of water and comes from Plato's Republic (X. 602c). The "oar in the water" illustration demonstrates how circumstances (contexts) can affect the individual's perception. Consider an oar half submerged in water. Beneath the water's surface the oar appears to be bent. It appears to have a different trajectory. Many have found this illustration trite. J.L Austin's comment reflects the modern attitude: "Does anyone suppose that if something is straight, then it jolly well has to look straight at all times and in all circumstances?" (Sense and Sensibilia, pages 21 and 29) However, Plato's illustration is less about sensibility than it is about his "two worlds" metaphysics. It is used to make his point that, since we can have only knowledge of Forms, we cannot have any false beliefs about Forms. What is below the surface, though refracted, is yet the very real projection of what is above the surface.

Austin appears to be unfamiliar with the Nilotic background of Plato's belief in universals. Indeed, this binary perception of reality was already ancient in Plato's time. Austin attempts to dismiss this, writing, “Ideally, I suppose, a discussion of this sort ought to begin with the very earliest texts; but in this case that course is ruled out by their no longer being extant. The doctrines we shall be discussing—unlike, for example, doctrines about 'universals'—were already quite ancient in Plato's time.”(Sense and Sensibilia, page 2) (Italics mine for emphasis.)

We do keep coming back to this binary feature. In telling the story of ontology, we cannot escape it. Our human anatomical structure, with bilaterialism, makes greater range of movement possible. Our bicameral brain/mind makes greater complexity of thought possible. Daily we are faced with the binary pattern of universal sets: male-female; night-day, and most significantly, life-death.

The mind makes distinctions along binary lines. We tend to think axiomatically: good-bad, normal-strange; one-many; now-not yet, etc. The mind recognizes that something can be and yet not be: the Biblical understanding of the Kingdom of God. Something can exist (actuality) while not yet existing. The kingdom is here now and yet still to come (potentiality), if we take Biblical eschatology seriously.

Aristotle's understanding of the elements now comes into play. He wrote, "The elements ... cannot be eternal. It is a matter of observation that fire, water, and every simple body undergo a process of analysis [i.e., destruction]. (On the Heavens 304b23). Fire can be destroyed by water. Water can be evaporated by wind/air. Vacuums exist, so air cannot be said to be everywhere at all times. And then there is earth, our final illustration.

The Greek comic poet and "wise man" Epicharmus (540-450 BC) was known to both Plato and Aristotle. He expressed a widely held ontological idea: "Life is compounded and broken up, and again goes whence it came; earth indeed to earth, and the spirit to upper regions." Many regarded the elements as deities. In this view, the gods are the winds, the water, the earth, the sun, the fire, the stars. To which Epicharmus quips: "But I think that the only gods useful to us are gold and silver."

Ben Sira (the author of Ecclesiasticus) writes, "How can dust and ashes be proud? Even in life the human body decays." (Ben Sira 10:9) He calls man "dust and ashes" and asserts that all things that are of the earth return to the earth. "Dust to dust. Ashes to ashes." The connection seemed obvious to those who came upon sites where humans had been buried long before and all that remained was an outline of ash and dust. This sight necessarily confronts us with the reality or unconcealment (aletheia) of our death as non-existence, what Heidegger termed "negation."

Negation means to deny, and Heidegger is concerned with a specific form of denial: the denial of one's non-existence, the refusal to face the reality of one's death. How we live and die tests the authenticity of our being. Awareness of my mortality changes how I live. For Heidegger, the proper response to being as a human is reflection on existence as a way to tug the veil that covers essence. We must do this to own our being as individuals living in the everyday world. We must look at the dust of the earth and say to ourselves, "That's what I am and to dust shall I return." Yet, as soon as we say those words, we know we have spoken a half-truth. The human is more than dust. We find ourselves turning from our well considered philosophical pretenses to language that has a God concept as its first order predicate. This has happened in the thought of many philosophers as they aged and approached death: Heidegger, Wittgenstein, and Derrida are examples. By avoiding the use of the word God and by replacing it with a god concept, they have unveiled a presence that has always been there. The presence serves as a function whereby existence is explored as second order extension. This "turning" (as Heidegger called it) appears to be a sign of authentication of individual being.

Søren Kierkegaard wrote, “Imagination is what providence uses to take men captive in actuality, in existence, in order to get them far enough out, or within, or down into existence. And when imagination has helped them get as far out as they should be - then actuality genuinely begins.” (The Two Ages)

Thursday, July 24, 2014

Interview with George Pattison

George Pattison
George Pattison is a philosophical theologian who thinks about contemporary religion, about how God cannot be separated from the quest for the Kingdom of God and cannot be an object of detached scientific contemplation. He thinks all the time on God and Being, on Heidegger on death, on the singularity, on the need for theology to engage with technology, on the new atheism, on links between Christianity and Japanese Buddhism, on Meister Eckhart, on Kierkegaard and avoiding sloppy scholarship, on keeping contact with unbelief, on the death of God and on resisting the idea of religion as heritage and instead orientating it towards hope. Soulful…

3:AM: What made you become a philosopher?

George Pattison: I’m not sure that I ‘am’ a philosopher – but I do engage with questions that are generally recognized as philosophical questions, such as the character of human existence and what makes for a good human life. In a sense these are questions that most people ask themselves to some extent. They become philosophical when asked with a persistence and rigour that pushes past conventional or evasive answers. It’s nothing to do with acquiring a technical facility in an academic discipline.

3:AM: Tillich and Barth are theologians of the beginning and mid last century very much tuned in to the humanist world laid waste and existentialist meaninglessness. You quote Beckett’s Estragon to capture the position theology talked to: ‘there’s no lack of void.’Kierkegaard, Nietzsche and Hegel too have been post boys for this position for some. Is this still a possible stance or is Cupitt right to say that the mourning is over and must stop?

GP: Perhaps this is an area where every generation starts from scratch. Although the crisis of the First World War inaugurated an especially strong period of disillusion with regard to the optimism of the previous age, the pattern has repeated itself in many ways in more recent times, e.g., the loss of faith in politics as a means of advancing human well-being. And perhaps this also has to do with basic elements in growing up. I still read a lot about teenage angst! Of course, any kind of mourning CAN become pathological and then it ‘has to stop’, but to move through life untouched by the loss of hopes, beliefs and aspirations once cherished is also questionable.

3:AM: What are the practices and claims of Derridean post-structuralist theology and why is it helpful in this post-theism context? Does Heidegger’s notion of ontotheology fit in with this?

GP: These are big questions. I’m not sure how far Derrida’s later ‘theological’ interests are really rooted in post-structuralism or whether they don’t rather reflect a kind of Kantian-Marxist trajectory—with a French twist on the centrality of liberty, equality and fraternity (cf. Politics of Friendship). Not to mention the role of Levinas and, behind Levinas, Judaism’s twinning of eschatology and the call for justice. What it does remind us is that ‘God’ is not to be separated from the quest for the Kingdom of God and is not and cannot be the object of any detached ‘scientific’ contemplation. Heidegger’s critique of onto-theology is also driving a wedge between speaking of God and the aims of science—not so as to get rid of God but rather to free God from a false objectification.

Read the full interview here.

Related reading:  George Pattison on Heidegger

Monday, April 21, 2014

The Shaping of 20th Century Ethics




Alice C. Linsley

Timeline

Charles Darwin             1809-1882
Soren Kierkegaard        1813-1855
Freidrich Nietzsche       1844-1900
Albert Einstein              1879-1955
Ludwig Wittgenstein     1889-1951
Rudolf Carnap              1891-1970
Martin Heidegger          1889-1976
Ayn Rand                     1905-1982
Elizabeth Anscombe      1919-2001
John B. Rawls               1921-2002
Jacques Derrida            1930-2004


Historians have reflected on the 20th century as a time of the great World Wars, the Holocaust, and the development of the atomic bomb. The United States begin the century in an isolationist mood, but was compelled to enter World War I as an ally to Great Britain and then World War II to confront the aggression of Hilter and as a response to the bombing of Pearl Harbor.

There was a mid-century baby boom in the United States as soldiers, sailors and airmen returned from the war to young wives eager to start families. These growing families needed housing and this lead to the development of track housing; Levittown being one of the most famous examples. Levittown is the model on which many post World War II suburban communities were based. It began as an experiment in low-cost, mass-produced housing and became the most famous suburban development in the world.


Albert Einstein

Einstein became a household name in the late 20th century. The applications of his theories lead to the development of the television, remote control devices, automatic door openers, lasers, and DVD-players. 

As a child, Einstein revealed an extraordinary curiosity for understanding the mysteries of science. He was particularly fascinating by the physics of light. His family moved first to Italy and then to Switzerland, where the young prodigy graduated from high-school in 1896.




In 1905, while working as a patent clerk in Bern, Switzerland, Einstein had his “miracle year.” He obtained his Doctorate degree and published four of his most influential research papers, including the Special Theory of Relativity which contained the now world famous equation e = mc2. This would unlock some of the mysteries of the Universe and forever change quantum physics, ethics and diplomacy. Einstein had much to say about the ethical ramifications of his discovery. He was known for his strong convictions on social justice, pacifism, and moral leadership. He once said, "Only a life lived for others is a life worthwhile."

In 1915, Einstein completed his General Theory of Relativity and in 1921 he was awarded the Nobel Prize in Physics. He emigrated to the United States in 1933 and took up residence in Princeton, New Jersey and held a professorship at the prestigious Institute for Advanced Study. In 1999, TIME magazine named Albert Einstein the “Person of the Century.”


Charles Darwin
A youthful Charles Darwin

The influence of Darwin’s writings, especially The Origin of Species, was pervasive and the cause of great debate. Darwin introduced the scientific theory that populations evolve over the course of generations through a process of natural selection. His writings presented evidence that the diversity of life arose by common descent through a branching pattern of evolution. Darwin included evidence that he had gathered on the Beagle expedition in the 1830s and through subsequent research.

Darwin’s ideas have been applied to social patterns in the works social Darwinians. In this view, societies exhibit evolution in that the social order is seen as the product of natural selection. Through Herbert Spencer, who coined the phrase “survival of the fittest,” and Darwin’s cousin Francis Galton, Darwinism and eugenics came together in the late 19th century. This relied on demonstrating that traits such as disease and lack of intelligence were inherited and that selecting against these traits would benefit society. The idea targeted the poor although history has shown that many great contributors to societal good have been people who began their lives in poverty. In the United States, eugenics persisted among the intellectual “elite” and was supported by racial discrimination. The involuntary sterilization laws, enacted in the early 1900s, were not repealed until 1979. The leading 20th century economist, John Maynard Keynes, was a staunch eugenicist who served as the director of the Eugenics Society in Britain from 1937 to 1944.

Eugenics became less attractive when many of the elite became poor as a result of the Great Depression and when the Holocaust atrocities became known. Social Darwinism along with the writings of Friedrich Nietzsche found expression in the Nazi dogmas. Nietzsche’s idea that the leader who wills to power is above the moral law embraced by ordinary men runs throughout Hitler's public utterances.


Ludwig Wittgenstein (1889-1951)

Wittgenstein is the leading analytical philosopher of the 20th century. He studied at Trinity College, Cambridge with Bertrand Russell. Russell inspired Wittgenstein to consider the nature of thought itself.  Russell was famous for statements like these:

“Thought is subversive and revolutionary, destructive and terrible. Thought is merciless to privilege, established institutions, and comfortable habit. Thought is great and swift and free.”

“Do not fear to be eccentric in opinion, for every opinion now accepted was once eccentric.”

Wittgenstein believed that words are human constructions without absolute meaning and that language is incapable of perfect communication. When we speak of a chair, for example, each of us has a different mental picture. Chair is really a word for various wood components that have been assembled in a certain way with nails or brackets. Or perhaps the components are metal and the chair folds. Of perhaps the chair is padded with cushions and upholstered with a colorful fabric.  So the word “chair” can produce different mental pictures.

Logical analytic approaches are concerned with the use of language, the logic of language systems, and the relation of language and mind. Wittgenstein influenced two important British philosophers: Elizabeth Anscombe and Philippa Foot.

Wittgenstein’s Tractatus Logico-philosophicus (1921), a volume of only 75 pages, became the Bible of the Vienna Circle. He believed that he provided the “final solution” to philosophical problems. In the Tractatus, he wrote that “philosophy aims at the logical clarification of thoughts” and philosophy is “not a body of propositions, but to make propositions clear.”

In Philosophical Investigations (1953), Wittgenstein argued that “philosophy is a battle against the bewitchment of our intelligence by means of language.” These two writings divide Wittgenstein’s work into two distinct phases. The two periods are not oppositional, however. In the Tractatus, he develops his thought about the logic of propositions, and in the Philosophical Investigations he is concerned about other forms of language and begins to explore the question more metaphysically.

Wittgenstein argued that language is composed of complex propositions that can be analyzed into less complex propositions until one arrives at simple or elementary propositions. Correspondingly, the world is composed of complex facts that can be analyzed into less complex facts until one arrives at simple or “atomic” facts. The world is the totality of these facts. So a chair is wood (or metal) and nails (or brackets) and fabric components as well as something upon which we sit.

In Wittgenstein's view this mental picture (chair) which we suppose gives us a true account of an object actually “stands in the way of our seeing the use of the word as it is” (PI:305). The picture of one thing, that is in fact many things, leads us to the childish belief that there is a correspondence between the word and the nature of the thing.

According to Wittgenstein’s picture theory, meaning requires that there be “atomic” facts.  This means that meaning is arrived at through analysis of only propositions that picture facts, or propositions of science.  By this reasoning, metaphysical and ethical statements are not meaningful assertions. Words such as good, evil and beauty do not represent simple propositions, so a statement such as “Murder is evil” is impossible to verify factually. Logical positivists, such as Rudolf Carnap, were influenced by Wittgenstein’s Tractatus. They soundly rejected all truth claims that could not be reduced to atomic facts. They also pushed metaphysical consideration of ethics aside, viewing it as a waste of intellectual energy.

This sort of discussion about language raised doubts about the meaning of words like “good” and “evil.” Some philosophers went so far as to say that these words are without meaning.  This would find support in Utilitarian ethics which stresses outcomes rather than motivations. Jesus’ teaching that evil comes from within the heart is set aside. Snip! Snip! Modern ethics is cut free from the Judeo-Christian tradition that sees evil and good as outward expressions of inward motivation.


Logical Positivism (1922-1950)

The philosophical movement of Logical Positivism can be traced to the Vienna Circle, a group of philosophers in Austria who held that experience is the only source of knowledge, and logical analysis using symbolic logic is the proper method for solving philosophical problems. This approach was popularized in Great Britain by A. J. Ayer and in America by Rudolf Carnap whose antimetaphysical views are set forth in such writings as The Logical Structure of the World (1928).

Logical Positivism held two key beliefs: (1) absolute confidence in empirical experience as the only source of knowledge; and (2) logical analysis performed with the help of symbolic logic is the single method for solving philosophical problems.  This group of philosophers attempted to exclude metaphysics from philosophical investigation in favor of strict logical and mathematical analysis. They also stripped ethics of aspects considered important from the earliest time: conscience, intuition, emotion, etc. The result was a materialist and empirical skepticism about all truth claims. The Logical Positivists were largely atheists who said that God doesn’t exist, or agnostics who regarded the existence of God as impossible to verify.

While skeptical about all truth claims that were not reducible as a mathematical formula, many Logical Positivists were optimistic about the capability of science to better the human race and life on earth. These shared a commitment to Unified Science; that is the construction of a system in which every legitimate statement is logically reduced to a direct experience. The Manifesto of the Vienna Circle stated that “The endeavor is to link and harmonize the achievements of individual investigators in their various fields of science.”

Logical Positivism was a highly academic approach that had little appeal to the average person who struggled with day to day moral choices. It also didn’t represent the religious sentiments of Wittgenstein, who called Soren Kierkegaard “a saint.”

Although only a few explicit references to Kierkegaard exist in Wittgenstein’s works, it is clear that Wittgenstein shared Kierkegaard’s religious inclinations. In conversation with his friend Maurice O'Connor Drury, Wittgenstein made the following remark:  “Bach wrote on the title page of his Orgelbuchlein, ‘To the glory of the most high God, and that my neighbor may be benefited thereby.’ That is what I would have liked to say about my work.”

A much as he may have wanted to be remembered for giving glory to God, Wittgenstein’s religious thought had little influence on 20th century ethics. On the other hand, the Tractatus influenced the development of Logical Positivism in Great Britain and the United States, and works published after his death influenced Idealism in Germany.

In Idealism, we find renewed interest in Platonism in reaction to an empiricism that has striped away metaphysical language. Idealism views the world as a mental construct with no objective existence independent of the Mind. All objects are fundamentally immaterial and a dimension of the mind. Objects exist but, they lack substance. Their existence necessarily requires their being perceived.

The Idealist can not say that anything physically exists. Idealism was expressed in the Immaterialism of the 18th century Irish bishop George Berkeley, and in the ego consciousness of the German philosopher Martin Heidegger.


Martin Heidegger (1889-1976)


The German philosopher Martin Heidegger succeeded his former mentor Edmund Husserl at Freidburg University in 1928. Husserl developed a philosophical theory called “phenomenology.”  He believed that philosophy could be as exact as science, claiming that phenomenological description is capable of a form of scientific positivism.

Heidegger dedicated his book Sein und Zeit (Being and Time) to Husserl and describes his method using Husserl’s term “phenomenology”, but the book represents a departure from Husserl’s thought. Heidegger was concerned with discovering the nature of being (ontology), specifically human being which he termed “Dasein.” The word is a compound of the German “da” which means there/here and “sein” which means to be. 

Heidegger exposes the fundamental problem of ontology, the definition of Being as being and influenced the work of Jacques Derrida. The significance of Heidegger's work was often downplayed because he was viewed as a Nazi sympathizer. There is little doubt that his failure to speak against the Nazi regime hurt his acceptance as an important philosopher. Another factor was the difficulty of understanding his writings which rely on subtleties of the German language.

Heidegger argued that humans do not create their world by mental pictures, but exist in the world and are shaped by the world. This means that each individual’s existence is unique. We see immediately that Heidegger’s work allows for an interpretative aspect that runs counter to the positivist claim that there can only be one right answer to a properly formulated logical problem. This is why Carnap, in a famous article, “The Elimination of Metaphysics" (1923), cited Heidegger’s work as an example of “philosophical nonsense.”

Heidegger’s Dasein deals with everyday human existence, not just the consciousness of the individual. It references the unique “human way of being”, a way of being that embodies an understanding of its mortality. Life leads to death and involves a dread of death. Heidegger believed that authentic being was possible only as the individual faces death honestly.

As with Nietzsche, Heidegger offered no hope of another world or another life beyond this one. We have only this life and that realization moves us to live this life differently. We each have a responsibility to act in the time we have to make life meaningful, but our being is only meaningful as it is seen against our movement to non-being or extinction.

Because there is no God and no moral structure to the world, each of us has a radical or “dreadful” freedom to choose our own world view, our lifestyle, and our moral standards. This is more than freedom. It is an inescapable existential necessity. The world is such that there is no escaping making a choice or escaping the consequences of our choices.

Heidegger’s thought implies a new definition of moral duty, one totally removed from the Judeo-Christian morality. The individual’s moral duty is not to obey God-given laws, but to face the reality of non-existence or negation. In What is Metaphysics? Heidegger poses these questions about negation:

Why are we concerned about this nothing?  The nothing is rejected by science and sacrificed as the unreal.  Science wants to have nothing to do with the nothing.  What is the nothing? Does the nothing exist only because the not, i.e., negation exists?  Or do negation and the not exist only because the nothing exists?  We maintain: the nothing is the simple negation of the totality of being (sein). Anxiety reveals nothing.


Elizabeth Anscombe (1919-2001)

The philosopher who most directly answers Heidegger is one of Wittgenstein’s students, G.E.M. ("Elizabeth") Anscombe, a devout Roman Catholic who smoked cigars and protested the practice of abortion. In 1968, when much of the intellectual world reacted with anger to Pope Paul VI's reaffirmation of Catholic teaching on contraception, Anscombe and her philosopher husband, Peter Geach, toasted the announcement with champagne. They had seven children. In the essay “Contraception and Chastity,” Anscombe defended Christian teaching on sex and marriage.  The essay was unpopular, but so intellectually rigorous that her opponents have never successfully refuted her argument.

Elizabeth Anscombe resourced in classical philosophy in her argument against Bentham’s utilitarianism. Against Locke's "natural law" theory, Bentham insisted that real rights are those established and enacted by the State. He proposed reforms, not on the basis of natural rights, but on the basis of his utilitarian "principle of extension." According to this principle, the "utility" or usefulness of a law depends on how widely the pains and pleasures of the law are felt across the spectrum of a society. This is the dominant approach in Post-Modern American politics.

Anscombe was one of the 20th century's most remarkable philosophers. She studied with Ludwig Wittgenstein, and upon his death in 1951 became one of his literary executors. She translated Wittgenstein's unpublished writings, preparing them for publication after his death, and she wrote a book entitled An Introduction to Wittgenstein's Tractatus. In 1970, Anscombe was appointed to the chair in Cambridge that had been held by Wittgenstein. Despite her loyalty to her former teacher, Anscombe was not one of Wittgenstein's true disciples. Her great intelligence and originality led her in different directions and to different conclusions.

In 1958, Anscombe produced a paper entitled “Modern Moral Philosophy” in which she offered a critique of prevailing academic approaches to ethics. In this paper she pointed out that while Aristotle had much to say about virtue and vices, he did not think of morality as people do today.  Our conception of morality comes from centuries of Christianity, drawing on Jewish law (Torah).  The Judeo-Christian conception of moral obligation is based on codified law.  From the first century A.D., Greek-speaking converts to Christianity sought to conform to virtues and avoid vices because these were viewed as a requirement of divine law.

Anscombe’s work restored interest among philosophers in the Aristotelian idea of virtue. Her paper on modern moral philosophy advanced “virtue ethics” in the 20th century. Her influence is seen in the work of Alasdair MacIntyre’s book After Virtue (1985) and Onora O'Neill’s book Towards Justice and Virtue (1996). She was also an important influence on the philosopher Phillipa Foot.

It was in the area of moral philosophy that Anscombe countered Heidegger’s bleak existentialism. She argued that since 20th century western society is no longer Christian, the terms “good” and “evil” or “right” and “wrong” are no longer useful. These terms are only meaningful as they are attached to the Judeo-Christian concept of a law-giving Creator God. Anscombe believed that in the post-Christian world many philosophers have become utilitarian, judging a right action by the best possible consequences. She pointed out that utilitarianism is incompatible with the Judeo-Christian insistence that some actions that are always forbidden regardless of the consequences. She recognized that Christian moral theology no longer has meaning for the Post-Christian world, and she proposed a way forward. She recommended discarding the notions of good and evil in favor of the notions of justice and injustice.

Let us consider Anscombe’s argument.  First, she assumes that the world is a place where the reasoning individual can be assured that concepts of justice, good, and moral obligation have meaning. This suggests that Heidegger’s “nothing” which causes us anxiety has a binary opposite – something – and this something potentially relieves anxiety. The logic of her argument is that when we feel the anxiety of injustice (which is negating) we should perform justice. Justice then is not a state of affairs, but a practical virtue of a good person. It is perhaps the derived virtue of being made in the image of a Good God.

Anscombe responds to Leibnitz’ criticism of conceptions of God as good. Leibnitz wrote: “It is generally agreed that whatever God wills is good and just. But there remains the question whether it is good and just because God wills it or whether God wills it because it is good and just; in other words, whether justice and goodness are arbitrary or whether they belong to the necessary and eternal truths about the nature of things, as do numbers and proportions (Reflections of The Common Concept of Justice). Anscombe’s common-sense argument is that humanity’s anxiety about death and negating injustice can only be experienced because humanity knows the Good. Her argument is the reverse of Heraclitus’ (540-480 BC) who said “If it were not for injustice, men would not know justice.”  Essentially, Anscombe is saying that the study of Man as subject leads logically to the conclusion that were it not for justice, humans would not know injustice.

The question of justice and how it is to be achieved becomes more complex in pluralistic societies where there are many competing interests.  How can a modern liberal democracy hope to have “liberty and justice for all” when the rule of the majority necessarily overrides the interests of minorities?  This problem was addressed by the American political theorist John B. Rawls.

Kant, Bentham, and Anscombe’s common-sense morality recognize that the moral agent must consider the interests of others. They recognize the possibility that sacrifices may be necessary to achieve a good end or a just society. Even Nietzsche recognized a potential place for sacrifice. Ayn Rand’s thought marks a departure from these thinkers.


Nietzsche and Kierkegaard: Different Directions in Existentialism

Nietzsche and Kierkegaard shared an overarching realization that anything meaningful or important must come from within the individual. It is the human race itself that attributes meaning. They both regarded the objective truth of the Enlightenment as a concept that ultimately leads to frustration, despair and anxiety. In Kierkegaard’s Fear and Trembling and in Nietzsche’s On the Genealogy of Morals, each philosopher sets out to discover the importance of subjective human emotion, and the role of human freedom in the universe. For Nietzsche there is no supernatural element, no knowledge to be gained by divine intervention or revelation.

Although Kierkegaard never used the term "existentialism" in his writings, he is regarded as the founder of Christian existentialism. Kierkegaard believed that the value of a philosopher's ideas should be judged by the person's life. He would have judged Nietzsche's perspective on the will to power as lacking moral and intellectual value. According to Kierkegaard, the individual’s life is the basis upon which he is judged by God. A writer's work is an important part of his existence, but his life as a whole is what ultimately matters to God.

Kierkegaard wrote, “If a human being did not have an eternal consciousness, if underlying everything there were only a wild, fermenting power that writhing in dark passions produced everything, be it significant or insignificant, if a vast, never appeased emptiness hid beneath everything, what would life be then but despair?” In this statement, Kierkegaard expresses “existential anxiety” or “angst.” Existential angst is not the same as normal fear. It is not caused by outside events that signal danger, it never leaves, it touches every area of our lives, and it does not respond to counseling. It is related to the universal anxiety felt about death.

Kierkegaard explained knowledge as miraculous or supernatural because it only can be initiated by God through a series of historical/temporal events. This learning or enlightenment is highly individual and subjective, and it is unique for every learner. He believes that individuals are unable to know anything that is certain except through this supernatural intervention in history.

What makes this learning or enlightenment possible? Human existence involves suffering, anguish, pain, sickness and death. That being our plight, we naturally desire an escape. This desire is very powerful. It is a yearning for the eternal that leads us to “leap into absurdity.” For Kierkegaard, it is the supernatural intervention of the divine Person Jesus Christ entering history, making it possible for us to know that God exists. The existence of God's existence can only be known by faith in this divine intervention that gives hope in this life and moves us from ignorance to enlightenment. Kierkegaard’s supernaturalism it is clearly the opposite of the Nietzsche's naturalism.


Ayn Rand (1905-1982)

Another view of how humans act in their own self-interest was developed by the Russian novelist Ayn Rand in her famous book The Fountainhead (1943). The title is a reference to Rand's statement that “man's ego is the fountainhead of human progress.”  In this book, and in her later volume Atlas Shrugged (1957), Rand lays down the ethical principle of rational self-interest that would become the basis for Objectivism.  She argues that rational selfishness is a virtue and that this virtue can be developed only by those who autonomously develop their own code of values and conduct.

Objectivism holds that individuals are in contact with an objective reality through sensory perception and that the proper moral purpose of one's life is the pursuit of personal happiness through acting in one's "rational self-interest".  Rand argued that the only social system consistent with this morality is laissez-faire capitalism. 

Rand advocated rational individualism and laissez-faire capitalism, and rejected socialism, altruism, and religion. She argued that it is rational only for one to seek to maximize one’s self-interest and that self-sacrifice for the good of others (altruism) is irrational.  Rand argues that selfishness is a proper virtue and that the rational person will pursue it.  She argued that the rational man lives “with his own happiness as the moral purpose of his life.”

Rand held that individual happiness involves choices and that “A code of values accepted by choice is a code of morality” (Atlas Shrugged). She wrote: “Man has been called a rational being, but rationality is a matter of choice — and the alternative his nature offers him is: rational being or suicidal animal. Man has to be man — by choice; he has to hold his life as a value — by choice; he has to learn to sustain it — by choice; he has to discover the values it requires and practice his virtues — by choice.”

Rand’s Objectivism is based on her view that the individual must elect to place self-interest as first priority in order not to become a “suicidal animal”. However, she never claims that there is a moral requirement to choose to value one's life.  To be moral is to choose that which promotes one's thriving in one’s personal context. There are no Kantian “categorical imperatives” that an individual would be obliged to carry out regardless of the consequences.

Rand’s ethical position assumes that rationality is the distinctive characteristic of human nature. In this she echoes the view of many philosophers, including Aristotle. However, her thought departs from Aristotle’s on a critical point: Aristotle believed that humans are political creatures and that reason is in the service of public life. Rand believed that humans are rational creatures whose service to public life should take the form of indifference.


John B. Rawls (1921-2002)

Rawls's theory of justice is posed as an alternative to the utilitarian approach that holds that the best consequences indicate the best political choices. In his book A Theory of Justice (1971), Rawls wrote “Each person possesses an inviolability founded on justice that even the welfare of society as a whole cannot override. Therefore, in a just society the rights secured by justice are not subject to political bargaining or the calculus of social interests” (Theory of Justice, p. 66).

Rawls proposed a social contract approach to justice that revolves around three principles: (1) each individual is to have equal right to the greatest personal liberty that is compatible with like liberty for all; and (2) social and economic inequalities are to be attached to public positions that are open to all under conditions of fairness in opportunity. Rawls also stated that when these principles are in conflict, the first principle must take priority.

Rawls accepts that there will always be some economic differences in society. He is not a Marxian. His concern is that those who are at the bottom should never be allowed to sink below the level of basic material needs. Fairness of opportunity requires consideration of those in society whose abilities may be such that they remain the least fortunate. To prevent extreme poverty, he developed a third principle which he called the “difference principle.”

Using the difference principle, Rawls hoped to minimize wealth differences by insisting that inequalities in basic goods can be allowed only if distribution of primary goods first benefits the poorest. He argued that the welfare of society depends on the welfare of the poorest, and that a just society makes fairness to all a primary consideration when forming public policy.

Rawls’ egalitarian approach to justice is a hypothetical one. It is not so much a philosophy as it is a method for constitution-building. He conducted his thought-experiment with his students at Harvard. Rawls’ method requires that participants forget their economic status, race, gender, level of education, religion, physical and mental abilities, etc. Under this “veil of ignorance” each is to consider fairness from an “original position.” They must establish a principle of fairness, such as distribution of income, without knowing beforehand where they end up in the pecking order. Rawls believed that nobody would agree to a system that incorporates unjust practices such as slavery or totalitarianism since they themselves might end up a slave or oppressed by the state. Rawls assumes that participants will always act rationally, and in seeking their best self-interest under the veil of ignorance, they actually will be seeking the best interest of all.

Rawls’ thought experiment operates on the assumptions that democracy is the best system, that people should vote, and that private property in not an inalienable right (against John Locke). His primary concern is justice. Rawls defends a welfare form of democracy on the basis that a just society requires that individual’s rights must always take priority over the common good. In his view that there is a fixed point of reference by which to decide justice. Rawls follows the deontological ethics of Kant.

Rawls developed a democratic system of determining distributive justice when people decide from a neutral or “blind” position. He proposes the following two principles of justice:

1. Each person has an equal claim to a fully adequate scheme of equal basic rights and liberties, which scheme is compatible with the same scheme for all; and in this scheme the equal political liberties, and only those liberties, are to be guaranteed their fair value.

2. Social and economic inequalities are to satisfy two conditions: (a) They are to be attached to positions and offices open to all under conditions of fair equality of opportunity; and (b), they are to be to the greatest benefit of the least advantaged members of society.

Rawls held that a person committed to justice for all as the highest self-interest can put himself in the “original position” and decide impartially. Rand, on the other hand, argues that justice for all is meaningless because nobody is able to reason impartially. Humans, in order to be human, act in accordance with what they think will promote their own best interest. To do otherwise, in Rand’s view, is to act as a non-rational animal.


Jacques Derrida (1930-2004)

Postmodernism moved away from traditional interpretations in the work of the French Algerian philosopher, Jacques Derrida, who sought to uncover the underbelly of meaning. Darwin on Heidegger, he explored "the metaphysics of presence." Heidegger maintained that Western philosophy has always granted primacy or “privilege” to presence itself. That is to say, something is because it can be and something can be because it is.

We might add that "something is not" is also about metaphysical presence. Derrida is familiar with the apophaticism of eastern thought.

Derrida focused on the ontological status of criticism and he established himself as a leading figure in deconstructionism. Deconstruction dismantles the underlying assumptions upon which a metaphysical argument is based. It requires detailed reading of a text, parsing of terminology, and language “freeplay” on the part of the critic.

Derrida's analysis of the Western philosophical project employs important descriptors such as: logocentrism, phallogocentrism, and ontotheology. “Logocentrism” emphasizes the primacy of logos or speech in the Western tradition. “Phallogocentrism” points to the patriarchal nature of this primacy. 

“Ontotheology” speaks of “the center" as a function to which we must return in unpacking the meaning. As Derrida said, “It would be possible to show that all the terms related to fundamentals, to principles, or to the center have always designated the constant of a presence, ... essence, existence, substance, subject, ... transcendentality, consciousness or conscience, god, man, and so forth.”

Postmodernism is characterized by skepticism toward all truth claims.  Traditional morals and values are seen as relative to one’s culture and place in society. This does not mean that all rejected the possibility of absolute truth. Derrida admitted that there is something at “the center” of reality, a function that is fixed for all people, though it is called by different names: Arche, Nous, God, Logos, the sacred center, etc.

Derrida saw Western Philosophy at a dead end. In his lectures series at Villa Nova University he suggested a possible remedy: recovery of the dynamic tension between Plato and Aristotle. He ascribes to objects a less substantial existence than the shadow they cast, or their trace. His reversals are a strategic intervention within the bounded Western philosophical system whereby he attempts to break out of that system.

As Derrida suggested: "Deconstruction cannot limit itself or proceed immediately to neutralization: it must, by means of a double gesture, a double science, a double writing, practice an overturning of the classical opposition, and a general displacement of the system. It is on that condition alone that deconstruction will provide the means of intervening in the field of oppositions it criticizes." (Metaphysics)


Summary

Throughout the 20th century, ethicists continued to address many of the key questions that have been considered from antiquity: human nature, the good life, moral authority, natural law, etc. However, modern science influenced ethical considerations in a profound way, especially the social sciences: Anthropology, Psychology, Sociology and Linguistics.

Ethics in the 20th century touched on matters beyond human freedom and moral choice. It questioned the very basis for making judgment about human existence, questioning even the ordinary words we use and the common ideas that we take for granted. Ethics in the 20th century is characterized by shifting points of moral reference, idealism, ammoralism, objectivism, linguistic analysis, and narrative deconstruction. Hume’s legacy is evident in the way that truth claims, especially religious claims, are regarded skeptically.

The 20th century also saw a proliferation of ideologies and philosophical developments. In logic, great new minds emerged such as Saul Kripe and Willard Van Orman Quine. They were influenced by the work of Gottlob Frege and Bertrand Russell.

Pragmatism emerged following Charles Sanders Peirce, William James and John Dewey. It has profoundly shaped American public education. With Dewey, Pragmatism became Darwin's theory of natural selection applied to educational philosophy.

Idealism insists that our notions of good and evil, as well as everything that we see or sense in the material world, are mental concepts with no objective existence. The existence of things depends on their being perceived in the mind. Idealism draws off Plato’s Forms and was further developed in the writings of George Berkeley.

Nietzsche’s views on power and German heroism fed Nazi propaganda during the Third Reich. The theme that the supreme leader is a law unto himself encouraged Hitler in his efforts to restore the glory of the Aryan race, a myth his propagandists had successfully planted in the German youth through indoctrination. Nietzsche’s ideas are found throughout Hitler's public utterances.

Wittgenstein said language is incapable of perfect communication. All language only approximates the object being described or discussed. By this reasoning, statements about good, evil and beauty don’t represent simple propositions, so a statement such as “Murder is evil” is impossible to verify using logic and math.

Logical Positivists, drawing off Wittgenstein’s Tractatus, are only concerned about “atomic” facts that represent things that can be verified and studied using strict logic and mathematical analysis. Most Logical Positivists are atheists or agnostics and sadly, many ended their own lives.

Heidegger believed the individual’s moral duty is to face one’s non-existence, what he called “negation”. Life involves a dread of death. Heidegger believed that authentic being is possible only when individual faces death honestly.

Anscombe believed that Bentham’s utilitarian ethics and Christianity are incompatible. She held to the validity of Natural Law. She believed that the Judeo-Christian concepts of good and evil are meaningless in post-Christian societies. She urged moving ethical discussion forward by using the concepts of justice and injustice. As with C.S. Lewis, who she debated in 1948 at the Oxford Socrates Club, Anscombe agreed that Christian catch words pose an obstacle to philosophical discussion. Lewis had written about the need to jettison such words in his Christian Apologetics. Anscombe proposed a similar way forward. She recommended discarding the words “good” and “evil” in favor of the words “justice” and “injustice.”

Rawls thought experiment is designed to establish a social contract or constitution based on ignorance of one’s position or status in that society. He hoped to minimize wealth differences by using the difference principle, the most widely discussed principle of distributive justice in the past half century. 

Rand sees rational self-interest as the single moral obligation. Rational selfishness is a virtue and self-sacrifice is irrational. Rand’s view of personal fulfillment differs from Aristotle’s because Aristotle believed that, as political creatures, humans must consider the happiness of others. Rand regarded political involvement with indifference and her ideal government allows citizens to live with the barest minimum of interference. This aspect of her thought has attracted much attention from Libertarians in the United States.