Friedman’s “Prediction vs. Explanation”

David D. Fried­man asks:

We do ten ex­per­i­ments. A sci­en­tist ob­serves the re­sults, con­structs a the­ory con­sis­tent with them, and uses it to pre­dict the re­sults of the next ten. We do them and the re­sults fit his pre­dic­tions. A sec­ond sci­en­tist now con­structs a the­ory con­sis­tent with the re­sults of all twenty ex­per­i­ments.

The two the­o­ries give differ­ent pre­dic­tions for the next ex­per­i­ment. Which do we be­lieve? Why?

One of the com­menters links to Over­com­ing Bias, but as of 11PM on Sep 28th, David’s blog’s time, no one has given the ex­act an­swer that I would have given. It’s in­ter­est­ing that a ques­tion so ba­sic has re­ceived so many an­swers.