The essence and composition of external bodies are so obscure, that we must necessarily, in our reasonings, or rather conjectures concerning them, involve ourselves in contradictions and absurdities.
 David Hume, A Treatise of Human Nature (1738). copy citation

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Author David Hume
Source A Treatise of Human Nature
Topic contradiction absurdity
Date 1738
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/4705/4705-h/4705-h.htm

Context

“It is commonly found, that in accounting for the operations of nature by any particular hypothesis; among a number of experiments, that quadrate exactly with the principles we would endeavour to establish; there is always some phaenomenon, which is more stubborn, and will not so easily bend to our purpose. We need not be surprized, that this should happen in natural philosophy. The essence and composition of external bodies are so obscure, that we must necessarily, in our reasonings, or rather conjectures concerning them, involve ourselves in contradictions and absurdities. But as the perceptions of the mind are perfectly known, and I have used all imaginable caution in forming conclusions concerning them, I have always hoped to keep clear of those contradictions, which have attended every other system.” source