Logic doesn't apply to the real world.

All intelligent problem solvers are subject to the same ultimate constraints - limitations on space, time, and materials.

What would a Martian visitor think to see a human being laugh? It must look truly horrible: the sight of furious gestures, flailing limbs, and thorax heaving in frenzied contortions.

But the big feature of human-level intelligence is not what it does when it is works but what it does when it's stuck.

Kubrick's vision seemed to be that humans are doomed, whereas Clarke's is that humans are moving on to a better stage of evolution.

Experience has shown that science frequently develops most fruitfully once we learn to examine the things that seem the simplest, instead of those that seem the most mysterious.

Eventually, robots will make everything.