we can only determine by imagination, which is not so powerfully affected by the future as by the present.
 Baruch Spinoza, Ethics (1677). copy citation

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Author Baruch Spinoza
Source Ethics
Topic imagination future
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

“consequently it would necessarily neglect a lesser good in the present for the sake of a greater good in the future, and would in no wise desire that which is good in the present but a source of evil in the future, as we shall presently show. However, we can have but a very inadequate knowledge of the duration of things (II. xxxi.) ; and the periods of their existence (II. xliv. note.) we can only determine by imagination, which is not so powerfully affected by the future as by the present. Hence such true knowledge of good and evil as we possess is merely abstract or general, and the judgment which we pass on the order of things and the connection of causes, with a view to determining what is good or bad for us in the present, is rather imaginary than real.” source