absolute beauty, for example, is always the same, whereas beautiful things continually change.
 Bertrand Russell, A History of Western Philosophy (1945). copy citation

Context

“that only what is complex can be dissolved, and that the soul, like the ideas, is simple and not compounded of parts. What is simple, it is thought, cannot begin or end or change. Now essences are unchanging: absolute beauty, for example, is always the same, whereas beautiful things continually change. Thus things seen are temporal, but things unseen are eternal. The body is seen, but the soul is unseen; therefore the soul is to be classified in the group of things that are eternal. The soul, being eternal, is at home in the contemplation of eternal things, that is, essences, but is lost and confused when, as in sense-perception, it contemplates the world of changing things.” source