well, there is the old story (quite probably made up) of neils bohr and the reporter who, while interviewing bohr, was surprised to find a horseshoe hanging on the wall of bohr's office. "surely mr.bohr", the reporter exclaimed, "a scientist such as you does not believe in supersititions such as the horseshoe bringing good luck?". "oh no i don't, of course", bohr responds n the story], "but they tell me it works even if you do not believe in it". i think, he most definitely would have said that to einstein about quantum theory. i would say it applies to any scientific theory or result.
perhaps you can tell your son that he doesn't have to believe in pythagoras on math, just has to use it (his theorem) since it works in some abstract cases, and knowing it well could make the difference in getting into stanford rather than uc berkeley!!! =:-O ;-)
--ravi
ps: just kidding about ucb of course - ucb is a holy spot for computer geeks such as i. and pkf used to teach there too...