Weak 'positive' evidence for Human ONLY formed crop circles:
The only known source of crop circles is human construction. Scientific inductive reasoning thus leads to the tentative
theory that ALL crop circles are constructed by humans. This theory can be falsified by presenting concrete evidence of ANY other source of crop circles which is not human in origin. This theory predicts that where the source of any specific crop circle becomes known, human construction will be found to be the cause. This prediction has been borne out in all known cases. This theory is not weakened by assertions that unevidenced causes of crop circles (such as cereal goblins or alien beings) might
exist anymore than evolutionary theory is weakened by baseless alternatives such as Last Thursdayism
How is the above claim any different to "evolution could NOT have happened because..." ?
Apart from anything else there is masses of positive evidence that evolution did occur. Provide some positive evidence of alien constructed crop circles and you can then maybe start making such comparisons.
If there is no evidence at all (one way or another) then I give everything equal scientific validity regardless of my personal opinion as to the liklihood.
In a vacuum of all evidence I would give all possibilities equal weighting too. But there is no such thing as a vacuum of all evidence. All human claims are made in the highly evidenced context of human psychology, history and culture.
To me, science is not about opinion or credibility it's about evidential support for a stated potential explanation.
Yes - Supporting evidence such as the evidence that humans can and do make crop circles.
By evidential support I mean accumulated failure to refute.
Our ability to conceive of unfalsified possible causes of crop circles (or indeed anything else) is limited only by our imagination. If faced with a crop circle of unknown origin you think science should give equal weighting to the human construction hypothesis, the farting celestial cow hypothesis, the alien construction hypothesis, the fluctuations in the matrix hypothesis, the underground morphic field hypothesis, the cereal goblin hypothesis etc. etc. etc. etc. - Then you obviously don't understand how scientific inductive reasoning made on the basis of positive evidence works.
If we accept 'unlikihood' as evidence against one thing, we must accept it across the board.
Nobody is citing unlikelihood as evidence. We are saying that any conclusion devoid of supporting evidence is unlikely to be correct.
Since there are many areas (ID being one) where we reject 'unlikihood' as sufficient, we cannot accept it anywhere else either without being hypocrytical.
You are conflating IDist claims of impossibility that fly in the face of the evidence with the argument being made here that completely unevidenced claims are unlikely to be correct. The fact that the word "unlikely" features in both does not make them the same.