What scientific idea is ready for retirement?  Read responses to that inquiry from the likes of Jared Diamond, Richard Dawkins, Alison Gopnik, Max Tegmark, Freeman Dyson, June Gruber, and many other brilliant people over at Edge.org , legendary book agent John Brockman's hub for really smart scientists and other big thinkers to share ideas with each other and the public. From the intro:
Science advances by discovering new things and developing new ideas. Few truly new ideas are developed without abandoning old ones first. As theoretical physicist Max Planck (1858-1947) noted, "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it." In other words, science advances by a series of funerals. Why wait that long?