Surely no child, and few adults, have ever watched a bird in flight without envy.

The Earth should not be cut up into hundreds of different sections, each inhabited by a self-defined segment of humanity that considers its own welfare and its own "national security" to be paramount above all other consideration.

It seems to me that God is a convenient invention of the human mind

Plate glass... has no beauty of its own. Ideally, you ought not to be able to see it at all, but through it you can see all that is happening outside. That is the equivalent of writing that is plain and unadorned. Ideally, in reading such writing, you are not even aware that you are reading. Ideas and events seem merely to flow from the mind of the writer into that of the reader without any barrier between. I hope that is what is happening when you read this book

They won't listen. Do you know why? Because they have certain fixed notions about the past. Any change would be blasphemy in their eyes, even if it were the truth. They don't want the truth; they want their traditions.

A fire-eater must eat fire even if he has to kindle it himself.

Unfortunately, in many cases, people who write science fiction violate the laws of nature, not because they want to make a point, but because they don't know what the laws of nature are.