For the historian of science, this uncertainty about the correct answer does have one important advantage. It undermines the tendency to judge past theories as being right or wrong by modern standards. This tendency is the so called "Whig interpretation of the history of science" that one usually finds in science textbooks and popular articles. The Whig approach is to start from the present theory, assuming it to be correct, and ask how we got there. For many scientists this is the only reason for studying history at all. ...
But Whiggish history is not very stisfactory if it has to be rewritten every time the "correct answer" changes. Instead, we need to look at the cosmogonies or planetogonies of earlier centuries in terms of the theories and evidence available at the time. (Pg. 4)
This tendency to judge by modern standards unfortunately goes far beyond science and infects the entire stream of popular history, particularly all discussions about women and the interactions of people of different races or creeds. It is meaningless to talk about whether women in different societies were more free or less free or whether certain societies were "tolerant." The real questions that should be asked are what circumstances lead to more hierarchical or egalitarian relations with the underlying assumption that there are no better or worse system just different equally reasonable reactions to different circumstances.