[AnotherUnixGeek]

just assume it's correct and legislate accordingly.

What legislation? SETI and similar projects have received some government funding but also plenty of private financing. Mind-exercises like the Drake equation are just intended to provide some initial framework for research and discovery - they don't deserve the uncomprehending awe the press always bestows on things like equations, but they do serve a legitimate purpose. Without such things we'd never have bothered looking for or finding extra-solar planets.

[papertyger]

What legislation?

It was in keeping with the analogy. There's no actual legislation involved unless you count educational standards.

Without such things we'd never have bothered looking for or finding extra-solar planets.

I disagree.

The fact that we knew planets existed makes it impossible to claim we'd never have looked for them elsewhere: just as we will look for life elsewhere.

But again, that is irrelevant. Looking for planets is nowhere near assigning probabilities for finding them...particularly when you've already admitted you have no idea what circumstances repeatably cause planets to form.