Some unspoken human communication is taking place on a hidden channel. I did not realize they communicated this much without words. I note that we machines are not the only species who share information silently, wreathed in codes.

Humans were still not only the cheapest robots around, but also, for many tasks, the only robots that could do the job. They were self-reproducing robots too. They showed up and worked generation after generation; give them 3000 calories a day and a few amenities, a little time off, and a strong jolt of fear, and you could work them at almost anything. Give them some ameliorative drugs and you had a working class, reified and coglike.

The world of the future will be an even more demanding struggle against the limitations of our intelligence, not a comfortable hammock in which we can lie down to be waited upon by our robot slaves.

Your soul is bigger than your programming.

He had them as spellbound as a room full of Ewoks listening to C-3PO.

It is not enough to live together in peace, with one race on its knees.

We already have the Wooden Pillar, the Steel Pillar and the Plastic Pillar. In a moment we will have the Golden Bail....'No, you won't.'We will,' stated the robot simply.No, you won't. It makes my ship work.'In a moment,' repeated the robot patiently, 'we will have the Golden Bail....'You will not,' said Zaphod.And then we must go,' said the robot, in all seriousness, 'to a party.'Oh,' said Zaphod, startled, 'can I come?'No,' said the robot, 'we are going to shoot you.'Oh, yeah?' said Zaphod, waggling his gun.Yes,' said the robot, and they shot him.Zaphod was so surprised that they had to shoot him again before he fell down. (85-86)