Everything you know is wrong

If by "you", I mean "science", and by "everything", I mean "most things":
In PLoS Medicine, John Ioannidis says:

There is increasing concern that in modern research, false findings may be the majority or even the vast majority of published research claims. However, this should not be surprising. It can be proven that most claimed research findings are false.

This paper is written in an opaque style, but Alex Tabarrok clears up the murk. Bayes rules!