A system is empirical or scientific only if it is capable of being tested by experience. These considerations suggest that not the verifiability but the falsifiability of a system is to be taken as a criterion of demarcation... It must… — Karl Popper Copy Share Image
A hypothesis is empirical or scientific only if it can be tested by experience. A hypothesis or theory which cannot be, at least in principle, falsified by empirical observations and experiments does not belong to the realm of science. — Francisco J. Ayala Copy Share Image
