4p1sc.md (1947B)
1 This proposition is more clearly understood from II. 2 xvi. Coroll. ii. For imagination is an idea, which indicates 3 rather the present disposition of the human body than the nature 4 of the external body; not indeed distinctly, but confusedly; 5 whence it comes to pass, that the mind is said to err. For 6 instance, when we look at the sun, we conceive that it is distant 7 from us about two hundred feet; in this judgment we err, so long 8 as we are in ignorance of its true distance; when its true 9 distance is known, the error is removed, but not the imagination; 10 or, in other words, the idea of the sun, which only explains 11 tho nature of that luminary, in so far as the body is affected 12 thereby: wherefore, though we know the real distance, we shall 13 still nevertheless imagine the sun to be near us. For, as we 14 said in II. xxxv. note, we do not imagine the sun to be so near 15 us, because we are ignorant of its true distance, but because the 16 mind conceives the magnitude of the sun to the extent that the 17 body is affected thereby. Thus, when the rays of the sun falling 18 on the surface of water are reflected into our eyes, we imagine 19 the sun as if it were in the water, though we are aware of its 20 real position; and similarly other imaginations, wherein the 21 mind is deceived, whether they indicate the natural disposition 22 of the body, or that its power of activity is increased or 23 diminished, are not contrary to the truth, and do not vanish at 24 its presence. It happens indeed that, when we mistakenly fear an 25 evil, the fear vanishes when we hear the true tidings; but the 26 contrary also happens, namely, that we fear an evil which will 27 certainly come, and our fear vanishes when we hear false tidings; 28 thus imaginations do not vanish at the presence of the truth, 29 in virtue of its being true, but because other imaginations, 30 stronger than the first, supervene and exclude the present 31 existence of that which we imagined, as I have shown in II. xvii. 32 33