A Zippy cartoon in which Pinhead parents deal with an exceptionally precocious child:
All three quotations have been attributed to Albert Einstein (hence the title, and the reference to Princeton in the last panel). They all look suspicious to me — especially the last, which some sites maintain was on a sign in Einstein’s office.
Sites that are scrupulous in sourcing Einstein quotations don’t seem to list any of them, and each of them appears on one or more sites that list quotes that are not attested from Einstein or or misattributed to him. (There are quite a few such spurious quotations attributed to him; Einstein, like Mark Twain and Winston Churchill and some others, is a “quote magnet”.)