The price we pay for our advance in civilization is a loss of happiness through the heightening of the sense of guilt.

The idea of life having a purpose stands and falls with the religious system.

Religion is comparable to a childhood neurosis.

By abolishing private property one deprives the human love of aggression.

Taboo restrictions are distinct from religious or moral prohibitions. They are not based upon any divine ordinance, but may be said to impose themselves on their own account. They differ from moral prohibitions in that they fall into no system that declares quite generally that certain abstinences must be observed and gives reasons for that necessity.

When it happens that a person has to give up a sexual object, there quite often ensues an alteration of his ego which can only be described as a setting up of the object inside the ego, as it occurs in melancholia; the exact nature of this substitution is as yet unknown to us.

The pleasure of satisfying a savage instinct, undomesticated by the ego, is uncomparably much more intense than the one of satisfying a tamed instinct. The reason is becoming the enemy that prevents us from a lot of possibilities of pleasure.