I suggest reading R. A. Lyttleton on the nature of knowledge: http://amasci.com/freenrg/bead.txt http://amasci.com/freenrg/bead.txt The scientific attitude to

I suggest reading R. A. Lyttleton on the nature of knowledge: http://amasci.com/freenrg/bead.txt http://amasci.com/freenrg/bead.txt The scientific attitude to adopt in regard to any hypothesis in my view (and we are talking of subjective things,) can be represented schemat- ically by means of a simple model of a bead that can be moved on a short length of horizontal wire (see diagram on next page). Suppose the left-hand end denoted by 0 (zero) and the right-hand end by 1 (unity), and let 0 correspond to complete disbelief unqualified, and the right-hand end 1 to absolute certain belief in the hypothesis. Now the principle of practice that I would urge on all intending scientists in regard to any and every hypothesis is: never let your bead quite reach the position 0 or 1 Once you're freed of the need to be absolutely certain of whether something is right or wrong, you can, in a more relaxed way, think about what the most sensible level of skepticism for any controversial issue about the way the world really is. Frinstance I'd say that the chance of creationism being right is something on the order of 10^-8. The chance of vaccinations being dangerous is maybe 10^-2, and the chances of them being more dangerous than the alternative maybe 10^-3. Peak oil? I dunno, 20%, depending what you mean by "peak oil". Holocaust denial comes in many forms from the lunatic to the nitpicky, each one needs its own level of skepticism. The "global warming" issue has quite unlikely positions on both sides with more plausible ones in the middle. And so on.