Famous quotes containing the words usual and/or system:
“The usual complaint is: I have no other way of earning a living. The harsh reply can be: Do you have to live?”
—Tertullian (c. 150–230)
“Science is a system of statements based on direct experience, and controlled by experimental verification. Verification in science is not, however, of single statements but of the entire system or a sub-system of such statements.”
—Rudolf Carnap (1891–1970)