It is a real wilderness, and those who go there should not feel too safe.

We read books to find out who we are. What other people, real or imaginary, do and think and feel... is an essential guide to our understanding of what we ourselves are and may become.

All knowledge is local, all truth is partial. No truth can make another truth untrue. All knowledge is part of the whole knowledge. Once you have seen the larger pattern, you cannot go back to seeing the part as the whole.

Paradise is for those who make paradise.

Dead anarchists make martyrs, you know, and keep living for centuries. But absent ones can be forgotten.

I went to the springs while the sun was still up, and sitting on a rocky outcrop above the cave mouth I watched the light grow reddish across the misty pools, and listened to the troubled voice of the water. After a while I moved farther up the hill, where I could hear birds singing near and far in the silence of the trees. The presence of the trees was very strong...The big oaks stood so many, so massive in their other life, in their deep, rooted silence: the awe of them came on me, the religion.

Science fiction - and the correct shortcut is 'sf' - uses actual scientific facts or theories for the source ideas or framework of the story. It has some scientific content, however speculative. If it breaks a law of physics, it knows it's doing so and follows up the consequences. If it invents a society of aliens, it does so with some respect for and knowledge of the social sciences and what you might call social probabilities. And some of it is literarily self-aware enough to treat its metaphors as metaphors.