In every age immorality has found no less support in religion than morality has. If the achievements of religion in respect to man's happiness, susceptibility to culture and moral control are no better than this, the question cannot but arise whether we are not overrating its necessity for mankind, and whether we do wisely in basing our cultural demands upon it.

A string of reproaches against other people leads one to suspect the existence of a string of self-reproaches with the same content.

The very emphasis of the commandment: Thou shalt not kill, makes it certain that we are descended from an endlessly long chain of generations of murderers, whose love of murder was in their blood as it is perhaps also in ours.

Love can not be much younger than the lust for murder.

There is scarcely room for doubt that something in the psychological relation of a mother-in-law to a son-in-law breeds hostility between them and makes it hard for them to live together. But the fact that in civilized societies mothers-in-law are such a favourite subject for jokes seems to me to suggest that the emotional relation involved includes sharply contrasted components. I believe, that is, that this relation is in fact an 'ambivalent' one, composed of conflicting affectionate and hostile impulses.

What good to us is a long life if it is difficult and barren of joys, and if it is so full of misery that we can only welcome death as a deliverer?

In the theory of psycho-analysis we have no hesitation in assuming that the course taken by mental events is automatically regulated by the pleasure principle. We believe, that is to say, that the course of those events is invariably set in motion by an unpleasurable tension, and that it takes a direction such that its final outcome coincides with a lowering of that tension that is, with an avoidance of unpleasure or a production of pleasure.