> I'd compare this to leaving your house's front door unlocked and open. You're an idiot, but if someone walks in and trashes the place, they still committed a

> I'd compare this to leaving your house's front door unlocked and open. You're an idiot, but if someone walks in and trashes the place, they still committed a crime. I disagree. The classic, respectable "value investor" takes advantage of other speculators mistakes by finding stocks who's value is irrationally low or high and betting against them. What's the moral difference? If automated trading systems can't handle someone playing back at them without causing a "flash crash" then that's an argument against letting automated systems trade (at least under current regs) not an argument against the opponents who outsmarted one.