Date: 1686, 1689, 1697

"The grand Instruments by which the Understanding works, are Memory and Invention: Now, since these Faculties have their foundation in the sensitive Capacity, as this Prop is withdrawn, the Understanding must of Consequence be more clouded and obscure."

— Nourse, Timothy (c.1636–1699)

Date: 1690, 1694, 1695, 1700, 1706

"At least they interpose themselves so much between our understandings and the truth which it would contemplate and apprehend, that like the medium through which visible objects pass, their obscurity and disorder do not seldom cast a mist before our eyes, and impose upon our understandings."

— Locke, John (1632-1704)