Where we have good, testable explanations, they then have to be tested, and we drop the ones that fail the tests.

Is the human race a universal constructor?

The theory that the biosphere was created without evolution, a few thousand years ago, is ruled out by overwhelming scientific evidence. To claim that there are 'alternative (always better) Biblical explanations of the same data', which make creationism a reasonable alternative to our best theories of biology and physics, is appalling intellectual dishonesty.

Despite the unrivaled empirical success of quantum theory, the very suggestion that it may be literally true as a description of nature is still greeted with cynicism, incomprehension, and even anger.

Feeling insignificant because the universe is large has exactly the same logic as feeling inadequate for not being a cow.

The whole [scientific] process resembles biological evolution. A problem is like an ecological niche, and a theory is like a gene or a species which is being tested for viability in that niche.

Like every other destruction of optimism, whether in a whole civilisation or in a single individual, these must have been unspeakable catastrophes for those who had dared to expect progress. But we should feel more than sympathy for those people. We should take it personally. For if any of those earlier experiments in optimism had succeeded, our species would be exploring the stars by now, and you and I would be immortal.