The truth is, many things are worth doing only in the most slovenly, halfhearted fashion possible, and many other things are not worth doing at all.

In sci-fi convention, life-forms that hadn't developed space travel were mere prehistory -- horse-shoe crabs of the cosmic scene -- and something of the humiliation of being stuck on a provincial planet in a galactic backwater has stayed with me ever since.

I realize that after decades of positive thinking the notion of realism, of things as they are, may seem a little quaint. ... When the stakes are high enough and the risks obvious, we still turn to people who can be counted on to understand those risks and prepare for worst-case scenarios. A chief of state does not want to hear a general in the field say that he 'hopes' to win tomorrow's battle or that he's 'visualizing victory'.

An asteroid could hit us at any moment. This is not - and also, the most successful kind of life on this planet is not us, it's microbes. They're the ones who greatly outnumber us, and may eventually destroy us.

At issue is not only knowledge of the world but our survival as individuals and as a species. All the basic technologies ever invented by humans to feed and protect themselves depend on a relentless commitment to hard-nosed empiricism: you cannot assume that your arrowheads will pierce the hide of a bison or that your raft will float just because the omens are propitious and you have been given supernatural reassurance that they will. You have to be sure.

It is the marketplace that calls most clearly for men to be softer, more narcissistic and receptive, and the new man is the result.

Middle-class-led reform movements, from the Progressive Era to the War on Poverty, have been marred by an elitist distance from the would-be beneficiaries of reform.