A difficult book to review, though it is a fairly easy read. Simak is a master of science fiction blending future technologies and their impact on society effortlessly into a novel.

Asher Sutton, is an investigator for the Beuro of Operations, overseeing humankind's vast galactic empire, which is partly formed through manind's pure agressive tendacies, and partly through the army of androids deployed. Asher is sent to Cynagi II to see if it is dangerous to humans, and returns after 20 years with the simple report that "it isn't" and declines to say anything else. This obviously leaves open many questions such as how he survived in his ruined spaceship, and why there is so mcuh android and human interest in his return. Some of these people seem to know too much, and have some very flimsy reasons for suggesting he should be shot on sight.

Simak deals effortlessly with the paradox time travel could create, through carefully written prose. The viewpoint is Asher's and he is always aware of his future, even as he lives in his own past.

The characters are fairly thin, but the worlds are clever, with interesting insight. There are some dated carryovers from when it was written. These days few would believe that in the year 3000 everyone would still be smoking.

Complex, clever, well written, a novel about what it means to be human, and how future technologies may change what we think, but can't change what we are.

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After re-read:
Not a lot more to add - there is some debate about the importance of religion, but essentially it is one of many books about what it means to be human. ( )