Date: April 26, 1695; 1708

"Meditating by one's self is like digging in the Mine; it often, perhaps, brings up maiden Earth, which never came near the Light before; but whether it contain any Metal in it, is never so well tried as in Conversation with a knowing judicious Friend, who carries about him the true Touch-stone, ...

— Locke, John (1632-1704)

Date: 1759

"His mighty mind travelled round the intellectual world; and, with a more than eagle's eye, saw, and has pointed out blank spaces, or dark spots in it, on which the human mind never shone."

— Young, Edward (bap. 1683, d. 1765)

Date: 1793

"It is curious to observe the first dawn of genius breaking on the mind. Sometimes a man of genius, in his first effusions, is so far from revealing his future powers, that, on the contrary, no reasonable hope can be formed of his success."

— Disraeli, Isaac (1766-1848)