You specifically mention Popper. Poppers criteria of falsification states that it is not enough that a theory can explain everything. He observed that a lot of

You specifically mention Popper. Poppers criteria of falsification states that it is not enough that a theory can explain everything. He observed that a lot of pseudoscience (astrology, marxism, freudian psychology at the time) really could be used to explain everything and couldn't really be disproved by any observation. Real scientific theories on the other hand could be used to make predictions which could be verified or shown to be wrong.