Is Hannibal Lecter insane?

Evil? Certainly. Sadistic? Often. Manipulative? Definitely. Insane? Not to me. Hannibal is definitely a sociopath if not a psychopath due to the lack of remorse he displays in his murders. However, he is quite logical in his thinking and his plans; he was also able to function perfectly fine in society before he was captured and he was very charming, thusly no one would have pegged him for a serial killer. He also doesn't target random people as a true psychotic person would; he typically kills if people are a threat to him or if they are simply rude to him. The fact that he eats his victims could be indication of insanity, but his ability to understand the consequences of his actions isn't something an insane person would have.