What is a defense mechanism?

Perhaps the most valuable mental asset is self-esteem,  a self-image that the individual likes and respects. Without it, we have little chance of possessing what philosophers and scientists have called by many names: a sound ego, an intact psyche, a healthy personality, a fulfilled self, or simply a wise and resourceful mind.

Small wonder, then, that human beings have an array of defenses to protect their self-esteem. Threats come in many guises, such as anxiety, guilt, shame, and conflict between two or more drives or emotions.

At times we consciously face these threats. Often, we automatically repress them, pushing them into our unconscious. Such repression may be the most basic ego defense mechanism, a term Sigmund Freud used to describe the ego's effort to resolve conflicts between the primal id, the moralistic superego, and external reality.