The list of "concepts that psychology really can't do without" includes such notions as neuronal connectionism, degrees of consciousness, mental representation of information, and dissociation. Of the pantheon of contributors to the history of psychology, Aristotle outranks all others in terms of the number of critical concepts he introduced, including the notion of the association of ideas, the law of frequency and the affiliated concept of memory strength, the notion of stage theories of development, the idea of distinguishing types of mental processes or faculties, the idea of scales of nature and comparisons between humans and animals, and last but not least, the pleasure principle. Unfortunately, computers don't always provide an unmixed increase in pleasure. Recent evidence suggests, contrary to what we might hope or suppose, that the computerization of the modern workplace has actually led to productivity declines. The negative impacts are likely due, at least in part, to the user unfriendliness of computers.