Belt

Scientific theories are never 'true or 'false'; they are 'good' or 'bad' in various degrees, and the criterion is one of usefulness-predictability and manipulation to (seeming) advantage. Theories are often discarded, simply because evidence may be insufficient for one, where it seems to sustain another-or where another can account for observed phenomena more simply. Take Lamarck's theories on the effect of environment on heredity; so far, the evidence seems to put this in the 'bad' classification. But if certain experiments could be made....