What I assume is that you remember an entire conversation where you assumed God but not heaven. If you don't, it's here:
http://www.poemranker.com/poem-details.jsp?id=119209. Notice I made more-or-less the same argument you're making now, to less effect. That is, at least when I assume God I assume God as the only real source of information we have about him makes him out to be. When you assume God you make him out of pillows to practice French kissing.