Ron Davies took a daft kind of risk, but Tony Blair should learn to chance his hand just a little more

Ron Davies, the bisexual MP so fond of the flora and fauna of Clapham Common, is undergoing psychiatric treatment to curb a "compulsive quest for risk". He blames the "problem" on a "troubled, violent and emotionally dysfunctional childhood". Davies talks of risk in the same way that Michael Douglas talks of sex or Tara Palmer-Tomkinson of coke: as a disorder that must be driven out at some swanky clinic in the desert.

In Davies's case, you can't help but hope it really will be pummelled out of him by some psychologist among the cactus plants: on the basis of any risk-reward analysis, his night-time stroll in a park notorious for gay pick-ups and drug peddling was a daft miscalculation.

He was cruising for a bruising in the same way that Bill Clinton was when he had oral sex in the Oval Office: for both men exposure was always likely, and its price always high.

How did they think they could get away with it? But that is just the problem with all risk addicts: they don't think. They feel only the gambler's urge for the quick fix and the adrenalin rush and seek only the danger of going against the odds. For these guys a safe bet is a dirty concept. If you tell the gambler glued to a slot machine that he is in a win-win situation, he will lose interest.

These cautionary tales don't mean that the rest of us should stop taking risks altogether. Indeed we couldn't: buying Internet stock, white-water rafting, eating Sunday beef, bearing a child at 40 . . . everything involves a certain risk. Even religion, as Pascal showed with his wager, can be seen as a gamble where you hedge your bets by believing in God - not much of gamble, admittedly, because you win if He exists and lose nothing if He doesn't.

In the casino of politics, the best players have always taken calculated risks. When Tony Blair tore up Clause Four or took his stand on the Balkans, he considered the odds, rolled that die - and raked in the chips. Voters loved it: a politician who takes a chance has balls; if you don't stick your head above the parapet, how can we see you?

But Blair's gambling instincts co-exist with a cautious mentality that opts for no-risk politics. This means listening to focus groups, rather than his gut; speaking in the spin-doctor's tried-and-tested phrases, rather than bursting into fire-in-the-belly oration; flirting with everyone and offending no one. Here formula replaces philosophy, and a safe pair of hands takes over from the inspirational leader who charges forth.

This kind of politicking often makes sense. Even the most wild-eyed poker player must have an occasional urge to control his environment and keep the risk minimal. As for the rest of us, we'll go to all kinds of lengths to stack the odds in our favour: we'll clamour about GM foods, boycott Belgian cola and take tests to make sure our child will be born healthy.

In politics the risk that makes our hair stand on end is the prospect of the euro: on the one hand, the gambler in all of us thrills at the thought of taking a leap on to a far greater stage; on the other, we are nervous about the threat to "nationhood" - though most of us are not quite sure what that means.

Blair has heard these anxieties and threatens to go all cautious on us. He should watch it - this is no moment to hedge his bets. While he considers his hand and decides how to play the euro, William Hague is suddenly transforming himself into a Cool Hand Luke: casting baseball cap and caution to the wind, he is taking a chance on the Europhobes, and the last elections showed that his move may pay off.

Risk-taking can be as great a virtue as a vice; caution as much a handicap as an asset. As he gets ready to deal with the euro, Blair should remember that sometimes you need to live a little dangerously to survive at all.