Date: 1159

"What is more remarkable, every one of us carries in his heart a book of knowledge, opened by the exercise of reason."

— John of Salisbury (c. 1115-1180)

Date: 1159

"In this [book of reason] are portrayed not only the forms of all visible things and nature in general; the invisible things of the Fabricator of all things are also written down by the very hand of God."

— John of Salisbury (c. 1115-1180)

Date: w. c. 1210

"The measuring line of his mind lays out the work, and he mentally outlines the successive steps in a definite order."

— Vinsauf, Geoffrey of [called Galfridus Anglicus] (fl. 1208-1213)

Date: w. c. 1210

"The mind's hand shapes the entire house before the body's hand builds it."

— Vinsauf, Geoffrey of [called Galfridus Anglicus] (fl. 1208-1213)

Date: w. c. 1210

"Let the mind's interior compass first circle the whole extent of the material."

— Vinsauf, Geoffrey of [called Galfridus Anglicus] (fl. 1208-1213)

Date: w. c. 1210

"As a prudent workman, construct the whole fabric within the mind's citadel; let it exist in the mind before it is on the lips."

— Vinsauf, Geoffrey of [called Galfridus Anglicus] (fl. 1208-1213)

Date: 1380-1387

"Thus gan he make a mirour of his minde, / In which he saugh al hoolly hir figure."

— Chaucer, Geoffrey (c. 1340-1400)

Date: 1384

"O Thought, that wroot al that I mette, / And in the tresorie hit shette / Of my brayn!"

— Chaucer, Geoffrey (c. 1340-1400)

Date: 1386-1400

"That oon of hem was blynd and myghte not see, / But it were with thilke eyen of his mynde / With whiche men seen, after that they ben blynde."

— Chaucer, Geoffrey (c. 1340-1400)

Date: 1389

"The soule ... muste suffre for the bonde of the body that he is joyned to."

— Trevisa, John (b. c. 1342, d. in or before 1402); Bartholomeus (1203-1272)