Famous quotes containing the words difference and/or principle:
“I never see any difference in boys. I only know two sorts of boys. Mealy boys and beef-faced boys.”
—Charles Dickens (1812–1870)
“Experimental work provides the strongest evidence for scientific realism. This is not because we test hypotheses about entities. It is because entities that in principle cannot be ‘observed’ are manipulated to produce a new phenomena
[sic] and to investigate other aspects of nature.”
—Ian Hacking (b. 1936)