For the mind feels those things that it conceives by understanding, no less than those things that it remembers. For the eyes of the mind, whereby it sees and observes things, are none other than proofs.
 Baruch Spinoza, Ethics (1677). copy citation

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Author Baruch Spinoza
Source Ethics
Topic proof mind
Date 1677
Language English
Reference
Note Translated by R. H. M. Elwes
Weblink http://www.gutenberg.org/files/3800/3800-h/3800-h.htm

Context

“Yet it is not possible that we should remember that we existed before our body, for our body can bear no trace of such existence, neither can eternity be defined in terms of time, or have any relation to time. But, notwithstanding, we feel and know that we are eternal. For the mind feels those things that it conceives by understanding, no less than those things that it remembers. For the eyes of the mind, whereby it sees and observes things, are none other than proofs. Thus, although we do not remember that we existed before the body, yet we feel that our mind, in so far as it involves the essence of the body, under the form of eternity, is eternal, and that thus its existence cannot be defined in terms of time, or explained through duration.” source