They [Bragg, Kendrew, Perutz] missed the alpha helix because of that
reflection! You see. And the fact that they didn't put the peptide bond in
right. The point is that evidence can be unreliable, and therefore you
should use as little of it as you can. And when we confront problems
today, we're in exactly the same situation. We have three or four bits of
data, we don't know which one is reliable, so we say, now, if we discard
that one and assume it's wrong--even though we have no evidence that it's
wrong--then we can look at the rest of the data and see if we can make
sense of that. And that's what we do all the time. I mean people don't
realize that not only can data be wrong in science, it can be misleading.
There isn't such a thing as a hard fact when yoou are trying to discover
something. It's only afterward that the facts become hard."
Art
http://chadwicka.swau.edu