Carl Sagan's Rules for Bullshit-Busting and Critical Thinking
<i>"Always ask whether the hypothesis can be, at least in principle, falsified. Propositions that are untestable, unfalsifiable are not worth much."</i><p>This. That's a good way to put it. I've mentioned Fred Hoyle's line on that, "Science is prediction, not explanation" (which is from one of Hoyle's novels), but Sagan's line is better.<p>Key point: unfalsifiable theories do not lead to useful technology. Engineering requires predictability.