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Experimental Evidence for the Existence of an External World


In this essay I attempt to refute radical solipsism by means of a series of empirical experiments. In the first experiment, I exhibit unreliable judgment about the primeness or divisibility of four-digit numbers, in contrast to a seeming Excel program. In the second experiment, I exhibit an imperfect memory for seemingly arbitrary three-digit number and letter combinations, in contrast to my seeming collaborator with seemingly hidden notes. In the third experiment, I seem to suffer repeated defeats at chess. In all three experiments, the most straightforward interpretation of the experiential evidence is that something exists in the universe that is superior in the relevant respects—theoretical reasoning (about primes), memorial retention (for digits and letters), or practical reasoning (at chess)—to my own solipsistically conceived self.

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