Sociopaths, like the rest of us, come in a full range of IQ's. The dumber ones tend to engage in carjackings and bank robberies. The smarter ones gravitate more towards Wall Street and politics, and some do quite well for themselves.
But no matter how smart a sociopath is, he will inevitably have certain intellectual weaknesses that stem primarily from his narcissism. Sociopaths inevitably think themselves better at everything than they are, and this is often their downfall.
Sociopaths often think they're fooling people when they're not. When a normal person is onto a sociopath, and realizes he's being lied to, he may just be too polite to say so, at least at first. The sociopath will take this as proof he's getting away with whatever lie he's promoting at the moment. Or, because he's successfully fooled people in the past, he thinks he will continue to get away with it in the future -- since, after all, he's so much smarter than everyone else.
Sometimes the lie is harmless, like insisting he hasn't had any plastic surgery when he obviously has. Other times, it's more sinister.
Similarly, sociopaths expect people to believe them when they claim to be turning over a new leaf, no matter how many times they've made similarly false statements in the past. And sociopaths always seem to think that they're fooling others with their displays of false emotionality. A sociopath always thinks he is disproving Abraham Lincoln's dictum.
Sociopaths, despite being masters of manipulation, are, ironically, quite easy to manipulate themselves. Because their egos are so out of control, they tend to believe whatever compliments they get. This makes them extremely susceptible to flattery. All you need to do is couch your request in a compliment ("You're far too smart to be doing that").
A sociopath is far more likely to surrender to his impulses, and compromise his future as a result. The seven deadly sins are in fact far more deadly when it comes to a sociopath. He'll let wrath get the better of him, and pull that trigger, or set that house on fire. He'll let lust get the better of him, and rape that girl. He'll let greed overcome him, and embezzle those funds. He'll even let curiosity get the better of him, and see how fast that car will go. And he's far more likely to indulge in drugs and drink, whatever the long term consequences.
He may regret all these things later, but it matters not at the moment, because "live for today" is the sociopath's motto.
Because a sociopath thinks little of the future, he is fearless when he should be fearful. ("I'm way smarter than those dumbass detectives, they'll never catch me."/"I know how to handle heroin, I'm not going to get addicted like those other idiots."/"I'm a great driver, I won't get in an accident.")
An alternative sociopathic motto might be, "Live fast, die young, and leave a surgically enhanced corpse."
Sociopaths tend to see themselves as victims, even when they are victimizers. So they never have a clear view of any complicated situation in which they have a vested interest. In their minds, everything that goes wrong is always someone else's fault. Since wisdom can only be gained by learning from one's mistakes, if you can never admit you're wrong, you can't learn.
So, sociopaths never develop good senses of judgment.
Sociopaths don't have the kind of patience it takes to calmly mull things over, so never really figure things out on their own and make great intuitive leaps -- the essence of true creativity. This, of course, does not stop them from taking credit for others' ideas, as Steve Jobs did.
(They are good at spur of the moment improvising, coming up with glib lies, and delivering them in a way so as to seem credible; but that is a different matter.)
In any case, all these egotistical quirks effectively render every sociopath stupid, no matter his IQ.
If you're aware of this, it will help you to deal with them more effectively. It should also help you avoid being sucked into a sociopath's self-destructive vortex.