So I have this theory; it links the monster (the black smoke), why Richard Alpert never ages, "The Incident," the purpose of the Arrow, the numbers, ect. It might link other things too.... So the Arrow, the place where Horace Godspeed worked (he was a mathematician), was the place where the Dharma Initiative tested electromagnetic energy in numbers. Some numbers would have too much harnessed electromagnetic energy, and some would have too little. The numbers (4 8 15 16 23 42) were the numbers that had the perfect amount of electromagnetic energy (that may be why the numbers are so "lucky"). "The Incident" was when some numbers that were tested had too much electromagnetic energy, and electromagnetic energy (that had the potential to be harnessed) escaped. That electromagnetic energy would be the monster that terrorizes the island to this day. Well, Richard Alpert was there when the electromagnetic energy escaped, and he was exposed to the large amounts of it, so he can't age anymore.