Against the suffering which may come upon one from human relationships the readiest safeguard is voluntary isolation, keeping oneself aloof from other people. The happiness which can be achieved along this path is, as we see, the happiness of quietness. Against the dreaded external world one can only defend oneself by some kind of turning away from it, if one intends to solve the task by oneself.

Just as a cautious businessman avoids investing all his capital in one concern, so wisdom would probably admonish us also not to anticipate all our happiness from one quarter alone.

Another technique for fending off suffering is the employment of the displacements of libido which our mental apparatus permits of and through which its function gains so much in flexibility. The task here is that of shifting the instinctual aims in such a way that they cannot come up against frustration from the external world.

Where id was, there ego shall be.

The division of the psychical into what is conscious and what is unconscious is the fundamental premise of psycho-analysis; and it alone makes it possible for psycho-analysis to understand the pathological processes in mental life, which are as common as they are important, and to find a place for them in the framework of science.

We are never so defensless against suffering as when we love.

It is a predisposition of human nature to consider an unpleasant idea untrue, and then it is easy to find arguments against it.