There are gems of thought that are ageless and eternal. – Cicero, quoted in Lillian Eichler Watson, Light from Many Lamps, 1951

Only roam on, therefore, all fearless, in the many garden of romantic chivalrous poesy, which drawing within its circle all that is glorious and inspiring, gave itself but little concern as to where its flowers originally grew. – C.O. Müller (Karl Otfried Müller), Introduction to a Scientific System

But further, in order to embellish it with flowers of language and gems of thought, it is not necessary for this ornamentation to be spread evenly over the entire speech, but it must be so distributed that there may be brilliant jewels placed at various points as a sort of decoration. – Cicero, De oratore

Precepts or maxims are of great weight; and a few useful ones at hand do more toward a happy life than whole volumes that we know not where to find. – Seneca