Every theory in philosophy, which is built on pure conjecture, is an elephant; and every theory that is supported partly by fact, and partly by conjecture, is like Nebuchadnezzar's image, whose feet were partly of iron, and partly of clay.
Thomas ReidThere is no greater impediment to the advancement of knowledge than the ambiguity of words. To this chiefly it is owing that we find sects and parties in most branches of science [and politics]; and disputes that are carried on from age to age, without being brought to issue.
Thomas ReidIn every case, we ought to act that part towards another, which we would judge to be right in him to act toward us, if we were in his circumstances and he in ours; or more generally - What we approve in others, that we ought to practise in like circumstances, what we condemn in others we ought not to do.
Thomas ReidIt is the invaluable merit of the great Basle mathematician Leonard Euler, to have freed the analytical calculus from all geometric bounds, and thus to have established analysis as an independent science, which from his time on has maintained an unchallenged leadership in the field of mathematics.
Thomas Reidmust acknowledge, that to act properly is much more valuable than to think justly or reason acutely.
Thomas Reid[I]f a man bred to the seafaring life, and accustomed to think and talk only of matters relating to navigation, enters into discourse upon any other subject; it is well known, that the language and the notions proper to his own profession are infused into every subject, and all things are measured by the rules of navigation: and if he should take it into his head to philosophize concerning the faculties of the mind, it cannot be doubted, but he would draw his notions from the fabric of the ship, and would find in the mind, sails, masts, rudder, and compass.
Thomas Reid