The Will to Power · Friedrich Wilhelm Nietzsche
484.
"Something is thought, therefore there is something that thinks": this is what Descartes' argument amounts to. But this is tantamount to considering our belief in the notion "_substance_" as an "_a priori_" truth:--that there must be something "that thinks" when we think, is merely a formulation of a grammatical custom which sets an agent to every action. In short, a metaphysico-logical postulate is already put forward here--and it is not merely _an ascertainment of fact...._ On Descartes' lines nothing absolutely certain is attained, but only the fact of a very powerful faith. If the proposition be reduced to "Something is thought, therefore there are thoughts," the result is mere tautology; and precisely the one factor which is in question, the "_reality_ of thought," is not touched upon,--so that, in this form, the apparitional character of thought cannot be denied. What Descartes _wanted_ to prove was, that thought not only had _apparent reality,_ but absolute reality.
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