He is a delusional narcissist who will fight until his last breath. Or an impulsive showman who will hop the next flight out of town when cornered. Or maybe he's a psychopath, a coldly calculating strategist - crazy, like a desert fox.
The endgame in Libya is likely to turn in large part on the instincts of Muammar Gaddafi, and any insight into those instincts would be enormously valuable to policy makers. Journalists have formed their impressions from anecdotes, or from his actions in the past; others have seized on his recent tirades about al Qaeda and US President Barack Obama.
But at least one group has tried to construct a profile based on scientific methods, and its conclusions are the ones most likely to affect American policy. For decades, analysts at the Central Intelligence Agency and the Department of Defense have compiled psychological assessments of hostile leaders like Gaddafi, Kim Jong-il of North Korea and President Hugo Chávez of Venezuela, as well as allies, potential successors and other prominent officials. (Many foreign governments do the same, of course.)
Diplomats, military strategists and even presidents have drawn on those profiles to inform their decisions - in some cases to their benefit, in other cases at a cost.
The political profile "is perhaps most important in cases where you have a leader who dominates the society, who can act virtually without constraint," said Dr Jerrold Post, a psychiatrist who directs the political psychology program at George Washington University and founded the CIA branch that does behavioural analysis. "And that has been the case here, with Gaddafi and Libya."
The official dossiers are classified. But the methods are well known. Civilian psychologists have developed many of the techniques, drawing mostly on public information about a given leader: speeches, writings, biographical facts, observable behavior. The resulting forecasts suggest that "at-a-distance profiling," as it is known, is still more an art than science. So in a crisis like the one in Libya, it is crucial to know the assessments' potential value and real limitations.
In a profile of Gaddafi, Dr Post concludes that the dictator, while usually rational, is prone to delusional thinking when under pressure - "and right now, he is under the most stress he has been under since taking over the leadership of Libya." At his core, Gaddafi sees himself as the ultimate outsider, the Muslim warrior fighting impossible odds, Dr. Post argues, and he "is indeed prepared to go down in flames."