Agreeableness: sociability and near psychopathy in the five factor model of personality
Agreeableness is a major personality dimension that determines how much you care about other people.
Low agreeableness differs from Autism in that autistics, lacking direct evidence, find it hard to know what other people are feeling while those low in agreeableness are perfectly capable of working out what other people are feeling but don't care.
Agreeableness is also the tendency to be pleasant and accommodating in social situations interpersonal interactions.
Women generally tend to score higher in agreeableness than men.
There is no evidence that high scorers are more likely to conform or be influenced by others than are low scorers, but the degree to which they take into account the feelings of others will affect how they display non conformity
Highly agreeable people
The high scorer tends to have an optimistic vew of human nature, and think most people are decent and trustworthy. They are considerate, helpful, and can feel what other people are feeling. They tend to give way in arguments rather than fight to the bitter end and may want to resolve a problem by consensus not coercion and are more likely to cotrol emotions like anger during a confrontation. As a result of all this they tend to be well liked and able to get what they want through negotiation rather than confrontation.
On the negative side the high scorer may become viewed as a doormat for others to walk over and may wear themselves out trying to please everyone. They may pass over opportunities in order to maintain good social relations, even when this is not necessary and may worry excessively about upsetting people. There is also a risk of dependency syndromes.
High scorers can make good counsellors but need to develop emotional armour to prevent emotional contagion from clients. They would also make good sales people if the work involved building client relationships.
Highly disagreeable people
The low scorer, as might be expected, has a pessimistic view of human nature and is low on trust. They tend to put their own interests above those of others and occasionally this backfires when others gang up on them. They are less popular but generally do not care about this. At an extreme, or when mental illness is present they may become narcissists and or antisocial. When they are also low in conscientiousness and neuroticism they may become indistinguishable from psychopaths, though such people are, fortunately, rare.
On the positive side the low scorer can be hardheaded and practical. They tend to be the sort of person who says what they think without sugar coating it, though they may do so if they feel it politically necessary. They do well in careers where they have to treat people like objects: club doormen, prosecution lawyers, politicians or civil servants for example.
The low scorer can mimic high agreeableness if necessary, the best example being politicians who have to develop excellent social skills to be elected but be hard headed and practical in determing policy (though they tend to fall under the sway of various other biases ). Note that the exercise of power tends to reduce the level of agreeableness
If you are someone with low agreeableness you should either be in a job where this is needed or be VERY good at what you do.
Note that success in anything tends to require low agreeableness. This is why the top levels of our society are by and large inhabited by people who are not very nice. This makes the few exceptions more remarkable,
Environmental pressures and regional variations
Different environments may select for high or low agreeableness and the rare low scorere in a society of high scorers will do well but in a society of low scorers the high scorer may do well. In his novel A Dirty Job Christopher moore puts it well if the high scorer is equated with the beta male and the low scorer to the alpha male. When the alpha males go to war the beta male stays in camp. Either the apha males are killed, in which case the beta male looks after the weeping widows, or they come back with more women in which case the beta male comforts the women who have been dumped. And there will always be widows.
There are regional variations and national variations in agreeableness. My observations are that the Dutch and Germans and Americans have, on average a lower degree of agreeablness than some other nationalities, though there are big regional variations in each country.
Nice or Nasty
There is no optimum level of agreeableness. Sometimes being ruthless is an advantage, sometimes it is not. The trick is to know your agreeeableness level and work with it.
Even a single individual's agreeableness may vary in the course of a day and between work and home.
I think the disagreeable person can become agreeable more easily than the agreeable person can become disagreeable, though a spell in prison may work the change, suggesting a criterion for prison policy - to create a climate where agreeableness is an advantage.