Daniel Bell's introduction to The Year 2000 : A Framework for Speculation on the Next Thirty-Three Years (1969) provides a handy half-prolegomenon for what Robin Hanson called "serious futurism":

More than forty years ago, Kegan Paul in England and E.P. Dutton in New York published a series of small books, about eighty in number, entitled Today and Tomorrow, in which some outstanding minds of the time made predictions about the future. The titles were romantic and metaphorical, and this provided a clue to the style and contents of the series...

What is striking about these volumes is their fanciful character, the personal and even prejudiced judgments, the airy and even comical tone, as if the idea of speculating about the future had a somewhat absurd but pleasant quality — in effect, a lack of seriousness... in no sense were these books mean to be anything more than "opinion"...

The uneven competence in the series is apparent as well in the writings of H.G. Wells, the man who inspired all these efforts. In his earlier book Anticipations... Wells predicted some social changes with startling accuracy, and fell flat on his face with others. The reason is that Wells was one of the first writers to see the importance of technology and to derive social consequences from specific innovations... But this reliance on technology gave a mechanistic cast to Wells' thinking, and led him to make some horrendous errors as well...

Reviewing the prophets of the past, one finds lacking in almost all of them — at least in their sociological predictions — any notion of how society hangs together, how its parts are related to one another, which elements are more susceptible to change than others and, equally important, any sense of method. They are not systematic, and they have no awareness of the nature of social systems... If there is a decisive difference between the future studies that are now under way and those of the past, it consists in a growing sophistication about methodology and an effort to define the boundaries... of social systems that come into contact with each other.