Tolerating organized crime promotes the cheap philosophy that everything is a racket. It promotes cynicism among adults. It contributes to the confusion of the young and to the increase of juvenile delinquency.

The hardest problems of all in law enforcement are those involving a conflict of law and local customs. History has recorded many occasions when the moral sense of a nation produced judicial decisions, such as the 1954 decision in Brown v. Board of Education, which required difficult local adjustments.

Circumstances of crimes vary. So do motives. And so do prospects for rehabilitation. The number of imponderables makes it impossible to sentence by formula and still sentence justly.

There are people in every time and every land who want to stop history in its tracks. They fear the future, mistrust the present, and invoke the security of a comfortable past which, in fact, never existed.

I'm not a luddite. Science, computers, medicine, they're all great. But nature is context. That which we can't control. Its constant mortality and immortality is an answer to the terror of finite existence. It reassures the soul.

When I was a teenager, science meshed with my developing ideals - such as the challenge to authority that was central to punk rock. In science, anyone from any walk of life could make a discovery that would overturn prevailing hypotheses. And that was a cause for celebration among scientists.

It takes a certain amount of courage to tackle very hard problems in science, I now realise. You don't know what the timescale of your work will be: decades or only a few years.

The belief that there are other life forms in the universe is a matter of faith. There is not a single shred of evidence for any other life forms, and in forty years of searching, none has been discovered. There is absolutely no evidentiary reason to maintain this belief.