Intellectualization is defined as the development and use of insights for self-deception rather than for tolerating and understanding affect. A concept of 'affect-thought ratio' is developed. Intellectualization does violence to this ratio as a defense against affect and passivity, especially in the transference reaction. It prevents 'true' insight in that it prevents optimal fusions of understanding and feeling. Intellectualization per se is not an indication of ego strength or weakness, although there are differences in the manner in which the weak and strong ego will use it as a defense. The whole subject of intellectualization and intellectual resistance is held to be important, too little studied, and in need of further study.