things in themselves are not, and cannot be, objects to us.
 Immanuel Kant, Critique of Pure Reason (1791). copy citation

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Author Immanuel Kant
Source Critique of Pure Reason
Topic
Date 1791
Language English
Reference
Note Translated by J. M. D. Meiklejohn
Weblink http://www.gutenberg.org/files/4280/4280-h/4280-h.htm

Context

“Reason goes its way in the empirical world, and follows, too, its peculiar path in the sphere of the transcendental. The sensuous world contains nothing but phenomena, which are mere representations, and always sensuously conditioned; things in themselves are not, and cannot be, objects to us. It is not to be wondered at, therefore, that we are not justified in leaping from some member of an empirical series beyond the world of sense, as if empirical representations were things in themselves, existing apart from their transcendental ground in the human mind, and the cause of whose existence may be sought out of the empirical series.” source