Books tap the wisdom of our species -- the greatest minds, the best teachers -- from all over the world and from all our history. And they're patient.

The lifetime of a human being is measured by decades, the lifetime of the Sun is a hundred million times longer. Compared to a star, we are like mayflies, fleeting ephemeral creatures who live out their lives in the course of a single day.

The cure for a fallacious argument is a better argument, not the suppression of ideas.

What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence.

The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small.

The well-meaning contention that all ideas have equal merit seems to me little different from the disastrous contention that no ideas have any merit.

Nevertheless, (Jefferson) believed that the habit of skepticism is an essential prerequisite for responsible citizenship. He argued that the cost of education is trivial compared to the cost of ignorance, of leaving government to the wolves. He taught that the country is safe only when the people rule.