Plastic surgery is stupid if it's just to make a person more beautiful. There are times when I think plastic surgery is fine, mostly for things like disfiguring injuries. But pumping your face and body full of chemicals and plastics to make your nose a little more straighter or your face rounder is stupid and really doesn't make any sense.
Makeup and other cosmetics is okay, as long as it's not over done. A little mascara or eye liner can help accentuate a person's looks better than if they weren't wearing any makeup. But the main difference as to why I think makeup is okay and plastic surgery isn't is because makeup is temporary. If you don't like it, you can always wash it off. You can always take out those contacts. They're not permanent, so they're more of an extension instead of a modification. A person that goes to have plastic surgery to make themselves believe they are beautiful are often, to me, uglier than someone who puts on a little makeup and is happy with what they got, even if after the surgery the person comes out as an 11.