Three loosely linked 1950s stories (brought together in paperback only, 1961), exploring the scientific pursuit of happiness. In the first, Hedonics, Inc., offers happiness for all: tough businessman Josh Hunt finds that, having rejected the proffered paradise, he isn't permitted to change his mind and re-enter (a theme repeated throughout Gunn's work). In the second part, the whole world is happy thanks to the efforts of the Hedonists, highly trained superman/psychiatrists--but hedonist Morgan finds that the ideal has been perverted: all Hedonists except himself have succumbed to the lure of power and fantasy, by substituting ""pleasure"" for ""happiness."" (He escapes from the Hedonics Council, with his girlfriend, to help terraform and colonize Venus.) And lastly, a sane society on Venus, based on Morgan's Hedonics teaching, is attacked by mechanical duplicates--while investigator D'Glas M'Gregor travels to Earth, where happiness has reached the ultimate degree: everyone has retreated into fantasy-fed artificial wombs, leaving a huge computer in charge. (D'Glas destroys the computer by instructing it that it too has to be happy.) Intriguing ideas and pointed social criticism--but Hedonics isn't much different from other superman-notions (like van Vogt's ""Null-A""), and the full-length treatment here is uneven, pulp-ish.