a) Humans are social creatures.
b) Agreement is a social activity.
c) Our feelings of comfort are satiated when someone agrees with
us.
This includes when people agree to disagree with each other,
because underlying the mutual fighting, is an agreement that
disagreement is a good thing. That is why enemies are often
closer than friends, because the enemy is, deep down, a deeper
friend because they agree to disagree and fight.
So, anything that involves agreement with others, to me, falls
into this.
