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al-Kindi, Yaaqub ibn Ishaq (800-872)

Islamic philosopher. As the first of the great Arab philosophers, al-Kindi sought to reconcile Greek philosophy with Islamic theology and originated the neoplatonic school of Islamic thought, emphasizing the priority of faith over reason, as later defended by Ibn Sina.

Recommended Reading: George N. Atiyeh, Al-Kindi: The Philosopher of the Arabs (Kazi, 1977).

Also see EB, SEP, and ELC.

κινησις [kinêsis]

Greek term for motion or change, a subject of great controversy among Greek philosophers. The Milesians took the facts of change and motion for granted until the Eleatics argued that motion of any kind is impossible; the atomists nevertheless supposed that change is a natural feature of all things. Aristotle argued that every change must be produced by some cause and regarded κινησις as the actualization of some potentiality {Gk. δυναμις [dynamis]} in the individual substance.

Recommended Reading: F. E. Peters, Greek Philosophical Terms: A Historical Lexicon (NYU, 1967).

Also see PP.

King, Martin Luther, Jr. (1929-1968)

American theologian and political activist. After completing his theological education at Boston University, King served as pastor of Baptist congregations in Montgomery, Alabama and Atlanta, Georgia and founded the Southern Christian Leadership Conference, organizing and leading significant social protests against racial discrimination in the American South until his assassination in Memphis, Tennessee. His "Letter from Birmingham City Jail" (1963) defends the use of I Have a DreamGandhi's method of non-violent protest as a powerful means of achieving social cooperation, and the "I Have a Dream" speech (1963) expressed a lofty vision of interracial unity. His writings include Why We Can't Wait (1964), Strength to Love (1966), and Where Do We Go from Here (1967). King was awarded the Springarn Medal, the Nobel Prize for Peace (1964), and the Presidential Medal of Freedom.

Recommended Reading: The Martin Luther King, Jr. Companion: Quotations from the Speeches, Essays, and Books of Martin Luther King, Jr., ed. by Coretta Scott King and Dexter Scott King (St. Martin's, 1995); The Autobiography of Martin Luther King, Jr., ed. by Clayborne Carson (Warner, 2001); Michael Eric Dyson, I May Not Get There With You: The True Martin Luther King, Jr. (Touchstone, 2001); David J. Garrow, Bearing the Cross: Martin Luther King, Jr. and the Southern Christian Leadership Conference (Morrow, 1999); and Charles Johnson, Bob Adelman, Robert Phelan and, Richard Woodley, King: The Photobiography of Martin Luther King, Jr. (Viking, 2000).

Also see EB.

knowledge {Gk. γνωσις [gnôsis]; Lat. cognitio; Ger. Wissen}

Justified true belief. Since Plato, nearly all Western philosophers have accepted this deceptively simple statement of the three necessary (and jointly sufficient) conditions for knowledge. That is, I know a proposition if and only if:

  1. I sincerely affirm the proposition,
  2. the proposition is true, and
  3. my affirmation is genuinely based upon its truth.
The correct analysis of each element of the definition, however, is open to question. Philosophers have held different views about the nature of belief and have proposed many different theories of truth.

Much of Western epistemology has focussed on the third element: precisely what constitutes adequate justification for knowledge? Rationalists and empiricists disagree about the sources which might provide relevant evidence, fallibilists raise practical doubts about our certainty in achieving the second condition, skeptics suppose that the third condition is never met, and contemporary philosophers since Gettier have questioned whether even the satisfaction of all these elements is genuinely sufficient for knowledge.

Recommended Reading: The Blackwell Guide to Epistemology, ed. by John Greco and Ernest Sosa (Blackwell, 1998); Contemporary Theories of Knowledge, ed. by John L. Pollock and Joseph Cruz (Rowman & Littlefield, 1999); Robert Audi, Epistemology: A Contemporary Introduction to the Theory of Knowledge (Routledge, 1998); A Companion to Epistemology, ed. by Jonathan Dancy and Ernest Sosa (Blackwell, 1994); and Jurgen Habermas, Knowledge and Human Interests, tr. by Jeremy J. Shapiro (Beacon, 1972).

Also see Norman Swartz, SEP on common knowledge and the analysis of knowledge, EB, CE, and DPM.

knowledge by acquaintance / knowledge by description

Russell's distinction between ways of knowing. Only the objects of immediate experience are known by acquaintance, through our direct awareness of them. Other things are known only by description, through the mediation of our apprehension of true propositions about them. For example:

"I have a headache now." may be known by acquaintance, but

"Aspirin will relieve a headache." can be known only by description.

Despite its apparently narrow extent, knowledge by acquaintance is supposed to provide the foundation for knowledge by description.

Recommended Reading: Bertrand Russell, Human Knowledge: Its Scope and Limits (Routledge, 1994); Bertrand Russell, The Problems of Philosophy (Oxford, 1998); and John G. Slater, Bertrand Russell (St. Augustine, 1994).

Also see SEP.

knowledge, theoretical {Gk. επιστημη [epistêmê], Lat. scientia}

An organized body of learning, the ultimate aim of human study for many classical philosophers.

Kripke, Saul Aaron (1940- )

American logician and philosopher. His early work, "A Completeness Theorem in Modal Logic" (1959) and "Semantical Considerations on Modal Logic (1963), focussed on technical issues in modal logic. In Naming and Necessity (1972) Kripke proposed a causal theory of referential meaning, on which proper names and natural kinds are not merely definite descriptions but rather rigid designators, whose reference must obtain in all possible worlds. On the basis of such semantics, Kripke holds that the necessary / contingent and a priori / a posteriori distinctions do not coincide. This raises significant doubts about theories that try to establish the contingent identity of mental events and brains states.

Recommended Reading: Saul A. Kripke, Wittgenstein on Rules and Private Language (Harvard, 1984); Scott Soames, Beyond Rigidity: The Unfinished Semantic Agenda of Naming and Necessity (Oxford, 2002); The New Theory of Reference - Kripke, Marcus, and Its Origins, ed. by Paul W. Humphreys and James H. Fetzer (Kluwer, 1999); and Consuelo Preti, On Kripke (Wadsworth, 2001).

Also see EB and ELC.

Kristeva, Julia (1941- )

Bulgarian-French literary critic and psychoanalyst influenced by the deconstructive methods of Derrida. In La Révolution du language poetique (The Revolution in Poetic Language) (1974) and Semeiotiche: Recherches pour une Semanalyse (Desire in Language: A Semiotic Approach to Literature and Art) (1980), she distinguishes between the pre-linguistic (feminine) semiotic of subjectivity on the one hand and the (masculine) symbolic representation of logic and language on the other. Kristeva describes ways in which literature (especially "feminine writing") can combine both in a joyful symbolic representation of the more fundamental semiotic reality. Powers of Horror (1981), Histoires d'amour (Tales of Love) (1983), and Soleil Noir (Black Sun) (1987) offer thorough analyses of horror, romantic love, melancholy, and depression. Kristeva's application of her central themes to political thought may be found in Etrangers à nous-même (Strangers to Ourselves) (1988).

Recommended Reading: Catherine Clement and Julia Kristeva, The Feminine and the Sacred (Columbia, 2001); The Portable Kristeva, ed. by Kelly Oliver (Columbia, 1997); The Kristeva Reader, ed. by Toril Moi (Columbia, 1986); Kelly Oliver, Reading Kristeva: Unraveling the Double-Bind (Indiana, 1993); John Lechte, Julia Kristeva (Routledge, 1990); Martha J. Reineke, Sacrificed Lives: Kristeva on Women and Violence (Indiana, 1997); and Michael Payne, Reading Theory: An Introduction to Lacan, Derrida and Kristeva (Blackwell, 1993).

Also see FTW and EB.

Kristina Wasa (1626-1689)

Queen of Sweden (from 1632) who pursued wide-ranging intellectual interests and corresponded with many of the seventeenth century's leading thinkers. Both Grotius and Descartes (to their peril) visited her court, and she published her Lettres de Descartes (Correspondence with Descartes) (1663). Kristina greatly admired the skepticism of Sextus Empiricus and Gassendi. After her refusal to marry led to a decision to abdicate the throne in 1654, Kristina first became an outspoken atheist and then converted to Catholicism.

Recommended Reading: Susanna Akerman, Queen Christina of Sweden and Her Circle: The Transformation of a Seventeenth-Century Philosophical Libertine (Brill, 1991).

Also see Bill Uzgalis, ELC, and EB.

Kuhn, Thomas Samuel (1922-1996)

American philosopher of science. In The Structure of Scientific Revolution (1962, 1970) Kuhn emphasized the discontinuity of scientific progress, characterized by long periods of "normal research" (conducted entirely within the framework of a prevailing theoretical paradigm) that are punctuated by brief and largely inexplicable periods of paradigm-shifting scientific revolution. On this view, there can be no rational grounds for choosing between incommensurable paradigms, each of which solves its own set of problems. Such themes are illustrated and expanded in The Essential Tension: Selected Studies in Scientific Tradition and Change (1977) and The Road Since Structure: Philosophical Essays, 1970-1993 (2000).

Recommended Reading: Thomas S. Kuhn, Black-Body Theory and the Quantum Discontinuity, 1894-1912 (Chicago, 1987); World Changes: Thomas Kuhn and the Nature of Science, ed. by Paul Horwich (MIT, 1994); Howard Margolis, Paradigms & Barriers: How Habits of Mind Govern Scientific Beliefs (Chicago, 1993); Alexander Bird, Thomas Kuhn (Princeton, 2001); , ed. by Thomas Nickles (Cambridge, 2002); Steve Fuller, Thomas Kuhn: A Philosophical History for Our Times (Chicago, 2000); and Hanne Andersen, On Kuhn (Wadsworth, 2000).

Also see SEP, EB, Andy Blunden, ELC, and Frank Pajares.


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