"the Greeks celebrated homosexuality and heterosexuality alike

So did the Romans. There is more than ample evidence of that in the Vatican library, which houses the word's largest collection of written pornography. Unfortunately it's all in Latin, and the wee devil sitting on my shoulder whispering in my ear says that the pages are probably all stuck together as well, but being a gentleman I would never say such a thing. I apologise unreservedly for his bad taste.