Here are some excerpts:
Of course, one can readily epitomize the ways in which these authors are significantly different . . . the characters that most interest them stand at opposite ends of the social spectrum . . . As Karl Marx would sum things up, Heinlein identifies with the aristocracy, Simak with the bourgeoisie, and Dick with the proletariat. More prosaically, the Heinlein Hero owns the office building; the Simak Hero runs a nice little shop on its ground level; and the Dick Hero sweeps his floors every night.
. . . it is not surprising that the polarizing changes in America during the 1960s moved Heinlein and Dick to opposite ends of the political spectrum. Heinlein, horrified by the counterculture and everything it represented, hardened into a bitter reactionary, eventually endorsing (in To Sail Beyond the Sunset) a longed-for President Patton’s policy of shooting drug dealers on sight. Dick embraced the counterculture, freely experimented with drugs, and announced a fervent admiration for young Americans and their liberal, liberating philosophies. For that reason, when commentators discuss the time when Heinlein happily purchased a new typewriter for a temporarily down-and-out Dick, this is presented as evidence of Heinlein’s amazingly generous spirit, his willingness to help individuals in need even if they were people he otherwise had reason to abhor.
I respectfully disagree. I think that Heinlein gave Dick a typewriter because he could recognize a soul brother when he saw one. And I would argue that, when one considers the qualities that made those writers great, the qualities that distinguish the wondrous novels and stories written in the first two decades of their careers, one must conclude that they are, in fundamental ways, exactly the same sort of writer.