"Evil" takes away from the old life in that Kino was happy before the pearl and its evil. Now he knows the pearl is worth something and he starts to consider ways to spend the money. This desire for money which at first was simply to save his son is now putting on the path of disaster. Thus the lure of the money from the pearl creates Kino's downfall and takes him away from the old life. Where he was happy not being officially married, without a gun and without an education for Coyotito, he now can't consider taking the low amount offered because he won't be able to get these new things; thing not available in the old life and are now only available because of the pearl and it's evil.