Today's topic (if we get to it after disussing recent issues of interest on the forum) will be:
He Who Says "Nothing Can Be Known" Knows Nothing
Skeptics hold that nothing in life can be known with confidence. The Skeptics of Epicurus' time argued, primarily due to their contention that the senses cannot be trusted, that we can never be certain of anything, and at most some things are "probable." Even something as obvious as the expectation that if you jump off a canyon wall you will fall to your death is not certain to such philosophers, it is merely "probable."
Epicurus saw that this confidence-destroying doctrine suffers much the same flaw as Determinism - it is self-contradictory nonsense. Anyone who is ridiculous and absurd enough to advocate that "nothing can be known" is taking you for a fool, because he expecting you to accept that he knows that "nothing can be known." Epicurus held that that such arguments should not be taken seriously, any more than you should seriously accept the argument from a living person that it would be better never to have been born.
Lucretius spoke for Epicurus in writing: " Again, if any one thinks that nothing is known, he knows not whether that can be known either, since he admits that he knows nothing. Against him then I will refrain from joining issue, who plants himself with his head in the place of his feet. And yet were I to grant that he knows this too, yet I would ask this one question; since he has never before seen any truth in things, whence does he know what is knowing, and not knowing each in turn, what thing has begotten the concept of the true and the false, what thing has proved that the doubtful differs from the certain? [Book 4:469]
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