There are eighty-eight notes. One hundred and seventy-six, if your ear is good enough to pick out quarter tones. Add in rests and so forth, different time signatures. Pick a figure for maximum number of notes a melody can contain. I do not know the figure for the maximum possible number of melodies—too many variables—but I am sure it is quite high.

"I am certain that it is not infinity.

Hear, hear. I have always wondered this. The old saw, "There's nothing new under the sun," is so true in so many cases. People will always be reinventing the wheel in the arts, but no matter what, every time they do it will be slightly different. There will be a new perspective, borne from a myriad of individual experiences coming together to form a unique viewpoint. So unless it's blatant and deliberate, I do think people ought to ease up on similarities and instead highlight the differences.

But they won't, as there's such an obsessive nature to protect one's creation, to the point of wanting utter control.