Cue the Creationist / New Ager / other Believer:
"But scientists once thought that, and now they think this!"
Yes. scientists continually update their beliefs to fit the evidence; that's the whole point, the whole beauty of science.
While no scientist has ever had trouble thus refuting the silly complaint above, I really like this quote from economist John Maynard Keynes, responding to an accuser charging him of inconsistency: Readeth thou more