Ontology quotes
52 quotes on this topic — from poets, philosophers, and thinkers across history.
"When I consider this carefully, I find not a single property which with certainty separates the waking state from the dream. How can you be certain that your whole life is not a dream?"
"All sentences of the type 'deconstruction is X' or 'deconstruction is not X', a priori miss the point, which is to say that they are at least false. As you know, one of the principal things at stake in what is called in my texts 'deconstruction', is precisely the delimiting of ontology and above all of the third-person present indicative: S is P."
"Neither the true nor the false roots are always real; sometimes they are imaginary; that is, while we can always imagine as many roots for each equation as I have assigned, yet there is not always a definite quantity corresponding to each root we have imagined."
"We admit, in geometry, not only infinite magnitudes, that is to say, magnitudes greater than any assignable magnitude, but infinite magnitudes infinitely greater, the one than the other. This astonishes our dimension of brains, which is only about six inches long, five broad, and six in depth, in the largest heads."
"Although my knowledge grows more and more, nevertheless I do not for that reason believe that it can ever be actually infinite, since it can never reach a point so high that it will be unable to attain any greater increase."
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Browse quotes that often appear alongside ontology — connected by shared ideas and recurring themes.
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"We must revisit the idea that science is a methodology and not an ontology."
"The line has magnitude in one way, the plane in two ways, and the solid in three ways, and beyond these there is no other magnitude because the three are all."
"There's something in the Western mind that gets very nervous when you try to talk about the bedrock of ontology."
"We call infinite that thing whose limits we have not perceived, and so by that word we do not signify what we understand about a thing, but rather what we do not understand."
"How dreadful knowledge of the truth can be when there's no help in truth!"
"Infinity is a fathomless gulf, into which all things vanish."
"To see what is general in what is particular, and what is permanent in what is transitory, is the aim of scientific thought."
"He who does not understand the supreme certainty of mathematics is wallowing in confusion."
"No human investigation can claim to be scientific if it doesn't pass the test of mathematical proof."
"Mystery is an inescapable ingredient of mathematics. Mathematics is full of unanswered questions, which far outnumber known theorems and results. It's the nature of mathematics to pose more problems than it can solve. Indeed, mathematics itself may be built on small islands of truth comprising the pieces of mathematics that can be validated by relatively short proofs. All else is speculation."
