Dan had a comment on the “science and proof II” posting that I think is of general interest that requires a fresh posting. He asks:
“Okay, do you have a quick explanation for why falsification is not the distinction between science and religion?
On a day to day level, it works for me. If someone says there exist leprechauns, but they are invisible, and leave no trace in our world, I know that the statement can not be proven wrong so it is not worth arguing against. But if someone says that species evolve from other species, it is conceivable that it could be proven wrong, so it is worth taking seriously. And if enough people try to disprove it and fail, that is good evidence that it might have explanatory power.”
Dan’s point is a good one. At a simple level, falsificationism sounds plausible. The theory that “All swans are white” can be seemingly falsified by the appearance of aa single black swan. Falsification’s appeal stems from the fact that we seem to be able to make a clean distinction between an observation and a theory.
But that distinction becomes blurred when you start looking at the kinds of things that scientists research, because then observations are no longer simple sensory perceptions. The statement “electrons exist” is not a simple observational one but requires us to use a vast array of theories from a range of disciplines in order to interpret the readings of the measuring insruments. So if the “observation” disagrees with the theory being examined, it is not clear where to place the blame. Is it on the theory being tested, or on one of the theories underlying the observations?
So in reality one is always comparing one set of theories with another set of theories and there is no rule that *forces* you to make a particular choice, although good taste and judgment and standard practices may lead the scientific community to a consensus decision.
The other problem with using falsification is that no theory has ever explained everything in its domain. There are always unsolved problems and contradictory results. Trying to reconcile these discrepancies serve as the basis for much research. If we applied the falsification rule strictly, then every theory we have would be falsified.
These are the kinds of things that caused falsificationism to stumble and fall.
Incidentally, even the swan example is not as simple as it looks. Defenders of the white swan theory can retain their belief by arguing that what constitutes a swan is not precisely defined and that the black creature was not really a swan, and other arguments like that. We may dismiss those arguments as silly and self-serving but they are not logically ruled out.
Warning! Shameless plug coming up!
All these issues are discussed in my book “Quest for Truth: Scientific Progress and Religious Beliefs”, published by Phi Delta Kappan Foundation in 2000.