Starting with Silvan Tomkin's theories of "innate affect," which provides the infant with neural systems allowing protective reactions to unwelcome stimuli, Nathanson develops the concept of an "empathic wall." Described as "a new ego mechanism," the empathic wall enables infants to define the difference between self and other, and protects them from unwanted or confusing states that result from intense affect. The author compares it to the defensive operations of denial and projection, and to projective identification. Clinical vignettes are given, illustrating the use of this concept with patients in therapy.