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Knowledge and justification



The evil genius argument

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Here is a very famous example of such an argument offered by Descartes it is known as the Evil Genius argument. From Descartes First Meditation: "Let me imagine, therefore, not that there does not exist a true God, who would act as the sovereign source of truth, but rather an evil demon, who is cunning, deceptive and powerful, and who employs every means he can to lie to me. Let me consider the possibility that all external things, the heavens, the air, the earth, colours, shapes and sounds, are only illusions and deceptions used by this demon to fool me. I shall consider the possibility that I actually have no hands, eyes, flesh, blood or senses, and only believe mistakenly that I have these things. I shall fix firmly on this idea, so as to find out whether it is within my power alone to arrive at the truth, or if not, to at least be able to maintain an impartial judgement. For this reason I want to be very careful not to believe in anything that is false, and in that way, I will prepare myself mentally against any trick that this powerful deceiver can impose upon me, whatever his powers of deception and cunning may be." Descartes uses this argument to undermine even our conviction that the truths of Mathematics and Logic are certain. Thus, global scepticism doubt of everything whatsoever is a possible conclusion of all these particular sceptical arguments, and the reader is warned that there will be many more to come in his experience as he delves further into Philosophy.
Contents of
Knowledge and justification

1 The distinction between knowledge and belief
2 Unsound, invalid, possible world and fallacy
3 Counterexample, exposing a fallacy
4 Belief and doubt
5 Believing that and knowing that
6 Knowledge and certainty - the tripartite definition of knowledge
7 True, justified belief
8 Plato: The Theaetetus
9 Plato: Forms
10 The possibility of scepticism and categories of belief
11 Global scepticism
12 The Argument from Authority
13 Valid argument, inference and justification
14 Chain of deductive inferences, self-evident truths
15 Sense experience, empiricism
16 The dialectic method, thesis and antithesis
17 Rationalism and empiricism; the Discourse on the Method
18 The Cogito, Reason and Rational Insight
19 Bertrand Russell, Acquaintance
20 Universals, Forms
21 Scepticism, Existentialism and Faith
22 The evil genius argument
23 Existentialism
24 Soren Kierkegaard - Fear and Trembling - the Absurd
25 Foundation for Knowledge
26 Theory of Knowledge, Epistemology and Metaphysics
27 Rationalism, Mathematics and Logic, Innateness
28 Innate Ideas
29 The a priori
30 Truth by convention, Hume and the Method of Doubt
31 Hume and the distinction between belief and knowledge
32 Hume and the definition of belief
33 Truth as a logical operator on sentences
34 The correspondence theory of truth
35 Wittgenstein: On Certainty
36 Wittgenstein and the coherence theory of truth
37 William James and Pragmatism
38 W.V.O. Quine, pragmatism and the Two Dogmas of Empiricism
39 Postivism and pragmatism
40 Pragmatism and utilitarianism
41 Pragmatism and religiion

Related articles: (1) Introduction to Plato, (2) Knowledge and justification