It's not bad-unless done obsessively.
The main distinction is from obsession to pleasure. Should one intend to gain pleasure from it, fine, but should one be addicted to the hormonal release, then it's bad. I'm not saying evil-evil is subjective.
Someone give me any argument against it. Most people could spot a flaw in them.
For example, an interesting one I found: "Masturbation makes you go blind"
Oh really? How on Earth does that work? There is no possible scientific basis for this.
I'm not even going to mention a separate document which states
a) it's better to get prostate cancer than to masturbate
b) masturbating out of curiosity is the same as going to a workplace/school, whipping out your genitals in front of anyone you vaguely admire, and starting to masturbate, while explaining how it's natural. It also says that, when facing a boss/expulsion committee, you should continue the demonstration until the police handcuff you. (If this makes sense to you, please visit either
http://en.wikipedia.org/wiki/Insane_asylum whilst looking for a new house, or
http://www.criticalthinking.org.uk/unit2/fundamentals/logicalfallacies/weakanalogy/ if you want to learn something).
Ok, so I did mention it.
Despite the social stigma, it's fine and natural, unless done compulsively. I'd say more than six times a week is compulsive. Seven times weekly is acceptable. Seven times daily is a sign of
a) stamina in your hands
b) friction burns
c) compulsiveness.