Date: 1692

"[T]he Explanation whereof is allowed by all men as satisfactory, 'tis this, in Tab. 41. Fig. 2. the Image a b of the Object A B is painted on the Retina inverted, and yet the Eye (or rather the Soul by means of the Eye) sees the Object erect and in its natural Posture."

— Molyneux, William (1656-1698)

Date: 1735

"Still can my Soul in Fancy's Mirrour view / Deeds glorious once."

— Somervile, William (1675-1742)

Date: January 1739

"In general we may remark, that the minds of men are mirrors to one another, not only because they reflect each others emotions, but also because those rays of passions, sentiments and opinions may be often reverberated, and may decay away by insensible degrees."

— Hume, David (1711-1776)

Date: January 1739

"On the other hand, impressions and passions are susceptible of an entire union, and, like colours, may be blended so perfectly together, that each of them may lose itself, and contribute only to vary that uniform impression which arises from the whole."

— Hume, David (1711-1776)

Date: January 1739

"Are not these as plain proofs, that the passions of fear and hope are mixtures of grief and joy, as in optics it is a proof, that a coloured ray of the sun passing through a prism, is a composition of two others, when, as you diminish or encrease the quantity of either, you find it prevail propo...

— Hume, David (1711-1776)

Date: January 1739

"The one seems to be, in a manner, the reflection of the other; so that all the perceptions of the mind are double, and appear both as impressions and ideas."

— Hume, David (1711-1776)

Date: 1742

"So engaging are the sentiments of humanity, that they brighten up the very face of sorrow, and operate like the sun, which, shining on a dusky cloud or falling rain, paints on them the most glorious colours which are to be found in the whole circle of nature."

— Hume, David (1711-1776)

Date: 1748, 1777

"When we reflect on our past sentiments and affections, our thought is a faithful mirror, and copies its objects truly; but the colours which it employs are faint and dull, in comparison of those in which our original perceptions were clothed."

— Hume, David (1711-1776)

Date: 1748, 1777

"And by this means, we may, perhaps, attain a new microscope or species of optics, by which, in the moral sciences, the most minute, and most simple ideas may be so enlarged as to fall readily under our apprehension, and be equally known with the grossest and most sensible ideas, that can be the ...

— Hume, David (1711-1776)

Date: 1751, 1777

"And, indeed, without such a correction of appearances, both in internal and external sentiment, men could never think or talk steadily on any subject; while their fluctuating situations produce a continual variation on objects, and throw them into such different and contrary lights and positions."

— Hume, David (1711-1776)