Although more than a thousand related articles were reviewed in our literature survey, no references were ever found in them or in their bibliographies crossing from one level, say the neurophysiology of the cell, to another, such as group psychology. In one article an offhand suggestion was found that such generalization might be possible, but it was apparent that in present-day behavioral science cross-level similarities are rarely considered and general systems properties seldom taken into account. This, despite the fact that at all levels comparable performance curves have been discovered. Since such general systems characteristics are not sought, the same phenomenon, with different names, different dimensions and units, is being discovered over and over again at different levels. Known for many years in neurophysiology, it is only recently being recognized at the individual level. Yet it is probable that, if information input overload causes similar performance curves and mobilization of comparable defenses at all levels of behaving systems, it can explain some of the psychopathology of everyday life and clinical practice.Abstract Teaser