Mary Fisher wrote:

I sometimes wonder why people who know everything bother coming on news
groups and trying to prove people wrong when they could be saving the world
:-)

Try Popper. While it's not universally true/accepted it's a fairly
good way of deciding whether things are factual/useful or not.

Popper surmised that one cannot prove that things aren't true, he said
that 'truths' which aren't falsifiable are pointless.

I don't think anyone is trying to prove that dowsing is wrong/untrue,
that's not really possible.

It's only that which can be proved to be true is generally useful.

--
Chris Green