QuoteThe Lovecraftian mythos comes from something other than atheism. It isn't nihilism, either.

Deists believed their rationality is mirror of Architect's rationality. HPL had no such delusion, so he noted that if that's how it is - then there is no reason to believe human mind is really attuned to understand how universe beyond their close proximity works - and further you go further even ability to comprehend ends. And as he was man of many fears, but also kinda admiring science - there there HORROR begin.

It's not really about seeking forbidden knowledge - plenty of HPL falls into HORROR without any hubris really leading them - and enemies are not failed science experiments, but if anything forces primordial. Horror lies in inherent inability of human mind to comprehend universe in it's essence.