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fact / value

Distinction between assertions about how things really are (fact) and how things ought to be (value). Drawn by Hume, but also defended by Stevenson, Hare, and other ethical noncognitivists, the distinction is usually taken to entail that claims about moral obligation can never be validly inferred from the truth of factual premises alone. It follows that people who agree completely on the simple description of a state of affairs may nevertheless differ with respect to the appropriate action to take in response to it.

Recommended Reading: David Hume, An Enquiry Concerning the Principles of Morals (Oxford, 1996) and Charles L. Stevenson, Ethics and Language (Yale, 1944).

Also see SEP and EB.


The contingent conditions of an individual human life. In the existentialism of Heidegger and Sartre, facticity includes all of the concrete details—time and place of birth, for example, along with the prospect of death—against the background of which human freedom is to be exercized.

Recommended Reading: Martin Heidegger, Ontology: The Hermeneutics of Facticity, tr. by John Van Buren (Indiana, 1999) and Alterity and Facticity: New Perspectives on Husserl, ed. by Natalie Depraz and Dan Zahavi (Kluwer, 1998).


A mistake in reasoning; an argument that fails to provide adequate logical support for the truth of its conclusion, yet appears convincing or persuasive in some other way. Common examples include both formal fallacies (structural errors in deductive logic) and informal fallacies (efforts to persuade by non-rational appeals).

Recommended Reading: Nicholas Capaldi, The Art of Deception: An Introduction to Critical Thinking (Prometheus, 1987); T. Edward Damer, Attacking Faulty Reasoning: A Practical Guide to Fallacy-Free Arguments (Wadsworth, 2000); and Douglas Walton, A Pragmatic Theory of Fallacy (Alabama, 1995).

Also see EB, FF, and GLF.


Belief that some or all claims to knowledge could be mistaken. Although Peirce limited the application of fallibilism to the empirical statements of natural science, Quine extended it by challenging the notion that any proposition can be genuinely analytic. Unlike a skeptic, the fallibilist may not demand suspension of belief in the absence of certainty.

Recommended Reading: Charles S. Peirce: Selected Writings, ed. by Philip P. Wiener (Dover, 1980); Charles S. Peirce and the Philosophy of Science, ed. by Edward C. Moore (Alabama, 1993); Roger F. Gibson, Enlightened Empiricism: An Examination of W.V. Quine's Theory of Knowledge (Florida, 1988); and Arthur Franklin Stewart, Elements of Knowledge: Pragmatism, Logic, and Inquiry (Vanderbilt, 1997).

Also see Kent Bach, Nicholas Burbules, and ISM.

false cause

The informal fallacy of affirming the presence of a causal relationship on anything less than adequate grounds. Post hoc, ergo propter hoc is a common variety of this fallacy.

Example: "After drinking milk for twenty years, Melanie became addicted to cocaine. Therefore, drinking milk caused her cocaine addiction."

Also see FF and GLF.


A property of any proposition for which it is possible to specify a set of circumstances the occurrence of which would demonstrate that the proposition is false. According to Karl Popper, falsifiability is the crucial feature of scientific hypotheses: beliefs that can never be tested against the empirical evidence are dogmatic.

Recommended Reading: Karl R. Popper, Logic of Scientific Discovery (Routledge, 1992) and Conjectures and Refutations: The Growth of Scientific Knowledge (Routledge, 1992).

Also see EB.

al-Faràbi, Abu Nasr (872-950)

Persian Islamic neoplatonist who employed Aristotelian logic in support of his arguments for the existence of god and used Plato's Republic as the model for his own description of civil society in Principles of Citizens of the Virtuous City.

Recommended Reading: Alfarabi: 'Philosophy of Plato and Aristotle', tr. by Muhin Mahdi, Charles E. Butterworth, and Thomas L. Pangle (Cornell, 2001) and Ian Richard Netton, Al-Farabi and His School (Curzon, 2000).

Also see EB and ELC.


Belief that every event is bound to happen as it does no matter what we do about it. Fatalism is the most extreme form of causal determinism, since it denies that human actions have any causal efficacy. Any determinist holds that indigestion is the direct consequence of natural causes, but the fatalist believes that it is bound occur whether or not I eat spicy foods.

Recommended Reading: Jordan Howard Sobel, Puzzles for the Will: Fatalism, Newcomb and Samarra, Determinism and Omniscience (Toronto, 1998) and Ted Honderich, Consequences of Determinism: A Theory of Determinism (Clarendon, 1990).

Also see SEP, ISM, and CE.

Feigl, Herbert (1902-1988)

Austrian-American philosopher. A member of the Vienna Circle of logical positivists, Feigl later taught at the University of Minnesota. He defended a materialist account of the human mind in The "Mental" and the "Physical" (1958).

Recommended Reading: Herbert Feigl: Inquiries & Provocations, Selected Writings 1929 to 1974, ed. by Robert S. Cohen (Kluwer, 1980) and Wilfrid Sellars, Empiricism and the Philosophy of Mind, ed. by Robert Brandom (Harvard, 1997).


Commitment to the abolition of male domination in human society. Feminists differ widely in their accounts of the origins of patriarchy, their analyses of its most common consequences, and their concrete proposals for overcoming it, but all share in the recognition that the subordination of women to men in our culture is indefensible and eliminable. Many feminist philosophers oppose Cartesian dualism, scientific objectivity, and traditional theories of moral obligation as instances of masculine over-reliance on reason. Serious attention to the experiences of women would offer a more adequate account of human life.

Recommended Reading: The Cambridge Companion to Feminism in Philosophy, ed. by Miranda Fricker and Jennifer Hornsby (Cambridge, 2000); The Second Wave: A Reader in Feminist Theory, ed. by Linda Nicholson (Routledge, 1997); A Companion to Feminist Philosphy, ed. by Alison M. Jaggar and Iris Marion Young (Blackwell, 1999); Seyla Benhabib, Judith Butler, Drucilla Cornell, Nancy Fraser, and Linda J. Nicholson, Feminist Contentions: A Philosophical Exchange (Routledge, 1995); Feminist Theory and the Body, ed. by Janet Price and Margrit Shildrick (Routledge, 1999); Sandra Harding, Whose Science? Whose Knowledge?: Thinking from Women's Lives (Cornell, 1991); and Eva Feder Kittay, Love's Labor: Essays on Women, Equality, and Dependency (Routledge, 1998).

Also see EB, SEP on feminist topics, epistemology and philosophy of science, social epistemology, ethics, political philosophy, history of philosophy, perspectives on the self, and approaches to the intersection of pragmatism and continental philosophy, Kristin Switala, Judit Hell, IEP, Krishna Mallick, and Olga Voronina.


Name given by medieval logicians to any categorical syllogism whose standard form may be designated as EIO-1.

Example: No mendicant friars are wealthy patrons of the arts, but some medieval philosophers are mendicant friars, so some medieval philosophers are not wealthy patrons of the arts.

This is one of the fifteen forms of valid syllogism.


Name given by medieval logicians to any categorical syllogism whose standard form is EIO-3.

Example: Since no people who admire Marx are political conservatives and some people who admire Marx are South Carolinians, it follows that some South Carolinians are not political conservatives.

This is another of the fifteen forms in which syllogisms are always valid.

Fermat, Pierre de (1601-1665)

French jurist and amateur mathematician. Although he engaged in a lengthy and bitter dispute with Descartes, Fermat worked together with Pascal on the development of the modern theory of probability. The famous "Last Theorem" Fermat proposed in a marginal notation—that for any n greater than 2, there are no integers that satisfy the equation xn + yn = zn —was proven only in 1994.

Recommended Reading: Michael Sean Mahoney, The Mathematical Career of Pierre de Fermat, 1601-1665 (Princeton, 1994); Simon Singh and John Lynch, Fermat's Enigma: The Epic Quest to Solve the World's Greatest Mathematical Problem (Bantam, 1998); and Morris Kline, Mathematical Thought from Ancient to Modern Times (Oxford, 1990).

Also see David Wilkins, MMT, WSB, and EB.


Name given by medieval logicians to a categorical syllogism with the standard form EIO-2.

Example: No people deserving of our admiration and praise are inveterate liars, but some wealthy industrialists are inveterate liars; therefore, some wealthy industrialists are not people deserving of our admiration and praise.

This is one of the fifteen forms in which syllogisms are always valid.

Feuerbach, Ludwig Andreas (1804-1872)

German philosopher. As a follower of Kant and critic of idealism, Feuerbach supposed that Hegel had mistakenly inverted the relationship between individuals and the Absolute. In Das Wesen des Christientums (The Essence of Christianity) (1841) he argued that religion is a projection of human values onto the concept of the divine. Eliminating the vestiges of theological dependence, Feuerbach maintained in Grundsätze der Philosophie der Zukunft (Principles of the Philosophy of the Future) (1843), will make it possible to avoid alienation and enjoy a thoroughly humanistic life.

Recommended Reading: Van A. Harvey, Feuerbach and the Interpretation of Religion (Cambridge, 1997).

Also see SEP, EB, and ELC.

Feyerabend, Paul (1924-1994)

Austrian-American philosopher. An outspoken opponent of Popper's philosophy of science, Feyerabend argued in Against Method (1975) that there is no privileged method for the confirmation of scientific theories. Thus, Feyerabend defended cultural pluralism and "scientific anarchism" in Science in a Free Society (1978), Farewell to Reason (1987), and Three Dialogues on Knowledge (1991).

Recommended Reading: Killing Time: The Autobiography of Paul Feyerabend (Chicago, 1996); John Preston, Feyerabend: Philosophy, Science and Society (Polity, 1997); and The Worst Enemy of Science: Essays in Memory of Paul Feyerabend, ed. by John Preston and Gonzalo Munevar (Oxford, 2000).

Also see SEP, Bas van Fraassen, ELC, , and Austria-Forum.

Feynman, Richard Phillips (1918-1988)

American physicist who contributed significantly to the development of modern quantum mechanics, the phenomena of superfluidity, and the nature of weak subatomic particle interactions. Feynman shared the Nobel Prize for physics in 1965. His colorful career and criticism of NASA are detailed in the autobiographical Surely You're Joking, Mr. Feynman (1984).

Recommended Reading: Richard Feynman, Six Easy Pieces: Essentials of Physics Explained by Its Most Brilliant Teacher, ed. by Paul Davies and Robert B. Leighton (Perseus, 1996), Six Not-So-Easy Pieces: Einstein's Relativity, Symmetry, and Space-Time, ed. by Gerry Neugebauer and Roger Penrose (Perseus, 1998), and The Character of Physical Law (MIT, 1967); and James Gleick, Genius: The Life and Science of Richard Feynman (Vintage, 1993).

Also see EB, MMT, and WSB.


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Last modified 26 December 2011.
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