Excerpt:
In 1934 Popper published what many regard as his Magnum Opus The Logic of Scientific Discovery. The famous chemist Wachtershauser said that this is a "gem" and that it liberated him from a sterile accounting view of science. Wachtershauser subsequently went on to develop one of the main theories of the origin of life. Frank Tipler, the famous cosmologist, regards this as the most important book this century. In one majestic and systematic attack, psychologism, naturalism, inductionism, and logical positivism are swept away and replaced by a set of methodological rules called Falsificationism. Falsificationism is the idea that science advances by unjustified, exaggerated guesses followed by unstinting criticism. Only hypotheses capable of clashing with observation reports are allowed to count as scientific. "Gold is soluble in hydrochloric acid" is scientific (though false); "Some homeopathic medicine does work" is, taken on its own, unscientific (though possibly true). The first is scientific because we can eliminate it if it is false; the second is unscientific because even if it were false we could not get rid of it by confronting it with an observation report that contradicted it. Unfalsifiable theories are like the computer programs with no uninstall option that just clog up the computer's precious storage space. Falsifiable theories, on the other hand, enhance our control over error while expanding the richness of what we can say about the world.