Certainly the nuns at my Primary School would have said so. And the Catholic Church definitely considered onanism to be a grievous sin, although it wasn't one I could ever bring myself to admit to at Confession (assuming that I did indeed indulge in this hideous practice). If I had done it (and I'm nor saying I did) I would have felt felt too guilty and embarrassed to own up to the priest on the other side of the grill. Even at that age I instinctively knew that bashing one's bishop could never be right. Although on the wickedness scale of original sin I guess a lot depends on the context. If you're married and you have a wank I don't suppose that's any better than committing infidelity. Or rather worse.
Or maybe indulging in the solitary pleasures is a victimless crime. Like insurance fraud. Except that isn't really victimless and somebody has to pay in the end (believe me - I've just had a quote for my house contents insurance - ouch).
On the other hand a friend of mine who was a keen masturbator used to defend the practice on the grounds that "You meet a better class of woman in your dreams."
It's not a subject you often hear debated dinner parties. I don't know why. Maybe because it's a solitary pursuit, spending hours alone in your room, fantasizing over something unobtainable.
A bit like blogging in fact. Except that blogging doesn't make you blind. Or deaf.
What? What was that? Speak up! For fuckss' sake's'. Jesus, where did I put the fucking keyboard?
At the end of the day whether it's right or wrong doesn't really matter. Just don't do it. Like taking drugs. A bit of self restraint. Come on guys, is that too much to ask? I bet women don't indulge in self-abuse. I can't believe they do. That really would shatter all my illusions. And without illusions onanism itself would simply die. Then there would be nothing left but blogging.
And what a terrible world that would be.