Ethics, Part V, Proposition 12
The mental images of things are more easily associated with the images referred to things which we clearly and distinctly understand, than with others.
Proof
Things, which we clearly and distinctly understand, are either the common properties of things or deductions therefrom (see definition of Reason, II. xl. note ii.), and are consequently (by the last Prop.) more often aroused in us. Wherefore it may more readily happen, that we should contemplate other things in conjunction with these than in conjunction with something else, and consequently (II. xviii.) that the images of the said things should be more often associated with the images of these than with the images of something else. Q.E.D.
Benedict de Spinoza, The Ethics (Ethica Ordine Geometrico Demonstrata), translated from the Latin by R. H. M. Elwes.
First published in The Chief Works of Benedict de Spinoza, vol. II (London: George Bell and Sons, 1884).
This translation is out of copyright in the United States, where it was published in 1884, and wherever the copyright term is the author's life plus 100 years or less; its translator died in 1892.
Unit divisions, headings and the placement of notes are this site's.
Digital text: Project Gutenberg eBook #3800