I think it is from Oscar Wilde, though I’m having a terrible time recalling or finding it.
IIRC, it says that the difference between a moral and immoral person is whether we like them, or share their vices, or something along those lines…I think.
Can anybody help?
That sounds a bit obvious to be from either Wilde or Shaw. The only thing at all similar I can think of is from Shaw’s Caesar and Cleopatra:
“You must forgive him, Caesar. He thinks the way of his tribe is the way of the World.”
A quick Google search turned up this:
But the one in my sig is much better. 
Is this it?
In his Preface to The Picture of Dorian Gray, Oscar Wilde writes;
“There is no such thing as a moral or an immoral book. Books are well written, or badly written. That is all.”
That’s it! Damn, I swear that I searched for quite a bit of time before asking. How embarassing.
Unfortunately, my memory of it was misleading. I wanted to forward it to a fellow who keeps talking about how we have to be “visionary” when his sole criterion for that status seems to be whether one agrees with him. I don’t think that is quite the flavor of the Wilde quote. C’est la guerre.
Thanks much!