to be in the mind and never to be perceived, is all one as to say anything is and is not in the mind or understanding.
 John Locke, An Essay Concerning Human Understanding (1689). copy citation

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Author John Locke
Source An Essay Concerning Human Understanding
Topic mind
Date 1689
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/10615/10615-h/10615-h.htm

Context

“mean such truths to be in the understanding as it never perceived, and is yet wholly ignorant of. For if these words “to be in the understanding” have any propriety, they signify to be understood. So that to be in the understanding, and not to be understood; to be in the mind and never to be perceived, is all one as to say anything is and is not in the mind or understanding. If therefore these two propositions, “Whatsoever is, is,” and “It is impossible for the same thing to be and not to be,” are by nature imprinted, children cannot be ignorant of them: infants, and all that have souls, must necessarily have them in their understandings, know the truth of them, and assent to it.” source