ABSTRACT
Work is the most ubiquitous form of human activity on the planet. In the strict physical scientific sense of the term (application of energy to drive chemical reactions (internal work) or to move body effectors (external work)), human engagement in work is synonymous with life itself, beginning at the moment of conception and terminating only with death. In the behavioral sense, all conscious human activity represents work directed at some sort of goal or another. In the occupational sense, all humans routinely engage in purposeful task or job work activity throughout most of their lives. In the evolutionary sense, since emergence of the species work activity has served both as the engine of the human condition and as the means of human self-selection.
