World leaders are often accused of hubris, of wielding power in arrogant and self-serving ways.
Leaders and managers in public life rarely escape criticism when they make unpopular decisions either. "The power has gone to his head" is an oft-heard accusation.
So are leaders losing touch with reality when they act in a power-hungry way?
According to psychologist Guy Claxton, professor of learning sciences at the University of Winchester, their actions could be to do with "a disorder of intelligence".
At a Royal Society of Medicine conference this week, entitled The Intoxication Of Power, Prof Claxton says that human intelligence is made up of four different mental systems working in harmony.
When one of these systems is not used, the decision-making process can become unreliable and potentially dangerous.
Instead of analysing actions, checking through the consequences of those actions and chatting through the decisions made, leaders too often rely on impulsive decision-making - and this is when hubris can set in.
"None of these systems is infallible. You need a jazz quartet of them to achieve full human intelligence," Prof Claxton says.
When it comes to governments and prime ministers, this failure of intelligence creates the need for ways of stopping power getting out of hand like the House of Lords checking the power of the House of Commons.
When individuals are in positions of great power, there are other dangers, he says.
"Politics can become dangerous. Leaders have the power to create wars."
When the rest of the world makes it known that they do not like this type of leadership, they tend to resort to something which Prof Claxton calls 'messianic hubris'.
"They transpose their leadership into a sense of humility, as if they are listening to an inner god or higher power when making decisions."
WHAT IS HUBRIS?
Hubris is defined as pride or arrogance and an excess of ambition - often in a position of power.
It comes from the Greek. In in classical Athenian usage, it meant the intentional use of violence to humiliate or degrade.
This is when self-deception and an inflated sense of self-worth sets in.
To combat against this, a sense of humour is a useful tool, Prof Claxton says.
"Traditionally, powerful people had a joker following them around, making jokes and poking fun at them, reminding them that they are just human beings."
This suggests that a reminder of your own fallibility is necessary when you are a leader in any field.
Another danger for powerful people is a potential lack of empathy for others, a subject also discussed at the Royal Society of Medicine conference.
Neuroscience studies have shown that the human brain responds to seeing someone in pain by activating pain in its own nerve endings, in order to mirror their pain.
Further research in this area suggests that if one person does not like another, for whatever reason, then feelings of empathy are less likely.
Dr Jamie Ward, reader in psychology at the University of Sussex, says that power has the same effect.
"You are less likely to imitate a low-status person if you are high status because you are unlikely to recognise or empathise with them. That could mean that the powerful are less empathetic."
Source: BBC News