Can we just say physical attraction isn't really something where humans have free will? I'm not that well read into biology/psychology (perhaps more than the average person in the street but not enough to claim academic expertise) and a conclusion I came to a long time ago is that it all comes down to geometry, or more crudely "curves in the right places" as driving the instinct to pursue whatever possesses the right geometry. There's a meme out there that puts a number of models into 'the golden ratio'/fibbonachi pattern that makes it painfully obvious that the further you deviate from this the less attractive you are...