From the back cover:

SURVIVAL TEST

Civilization had grown so complex that only a world-wide computer network could control everything. But the computer was only logical -- it lacked common sense. And its all-too-logical decisions were beginning to cause too many near fatal accidents.

The solution was on the drawing boards -- a universal self-aware and self-programming computer, equipped with judgment. But... could it be controlled? Or would it attempt to take over, disregarding its creators? If so, could it be turned off?

Raymond Dyer and his team of computer specialists knew they had to find answers to these questions, but the project was to dangerous to test on Earth. So they installed the super computer on an orbiting satellite and programmed it to survive at all costs. Then they sent a group of men to attack the computer... to goad it into trying to kill them. They they would turn it off.

Obviously if things went wrong, they might lose a few men -- but the satellite and the computer could always be destroyed.

Obviously...

But the computer didn't quite see it that way!