@edgarblythe,
Of course you don't have to ed. You couldn't anyway.
But do you think you would be living as you do if everybody agreed with your contention and had always done so. Where would atheists have started the Western cultural project from?
Human beings have had 2, some say 4, million years to get the science of dynamic space up and running. Are you saying that it was mere coincidence that such a dramatic event took place in the Christian cultural setting?
How do you know anybody in it believed in God rather than acting as if they did.
If by an invisible block of granite you mean it's in the dark and I can't see it I would probably have a glance upwards even if I had already discovered what a chump you are. If you mean the block is unseeable I would pat you on the noddle. As I would also if my doing so was said to be going to cause it to fall. That's voodoo.
I could believe you for as long as it took me to take a few paces to one side and then switch to not believing you just to see if my unbelief could re-direct the unseeable granite block to my new position or have it follow me around.
Meanwhile--the church bells are ringing to call decent folk to their praying and singing--and to their endogamous courtship rituals, piss-ups, employment opportunities and real-estate stitch-ups.