The tactile sense is primary-it is the first to emerge in the developing fetus at about eight weeks. It is a crucial defense mechanism and therefore essential to survival. The tactile sense helps distinguish between multiple distinctive perceptions, each of which can be experienced on a range, such as deep versus light touch, soft versus hard, sharp versus dull touch, as well as the sensations of heat and pain.

Each one of these components affects our experience of the environment and protects us from the dangers in it. Touch sensation is pleasant or annoying, comforting or irritating, reassuring or anxiety-provoking. It makes us want to linger in an experience or to move away from it as quickly as possible. Meret Oppenheim's 'Object', below, is a wonderful illustration of the suggestive power of touch.