Soldato
- Joined
- 8 Mar 2007
- Posts
- 10,938
No, we can't rule it out, but the time to believe in something is when there is evidence for it.
Suppose someone claims that unicorns exist. To prove it, all you need to do is present one unicorn. To disprove the statement is effectively impossible. You can't examine the entire universe simultaneously in order to say definitively that unicorns don't exist. The burden of proof lies with the person making the claim.
The hypothesis that we are testing - Unicorns exist.
The null hypothesis - Unicorns don't exist.
Suppose a unicorn is presented. Then we accept that unicorns exist and reject the null hypothesis. Suppose a unicorn isn't presented. Then we reject the hypothesis that they exist as there is no evidence to support that. This does not mean that we accept the null hypothesis. The best we can do with our limited knowledge is fail to reject it. This is why we have "not guilty" rather than "innocent" in a court. Innocence is the null hypothesis, but you can never prove innocence outright. The best we can do is to say that the prosecution have not met their burden of proof, hence not guilty.
Q.F.T