Popper, Karl (1902-1994) Distinguished philosopher of science and spoil sport. Popper asserted that you cannot have scientific principles unless they can be subject to disproof or test, and that the spirit of science is to make wild and unfounded conjectures, and to challenge them unmercifully. This Socratic spirit of informed self-doubt is thankfully not needed in psychology, where every year we get new books full of untestable conclusions that purport to explain it all, without a doubt. (see Steven Pinker)
