[caslon]

> My comment is a theoretical example (or thought experiment)

That goes against all evidence and all studies on the topic and has no supporting evidence to back it up.

[bscphil]

Premise: there are no colorful swans

Conclusion: all swans must be either grey or white

Me: that doesn't follow! Suppose there were a black swan.

You: That goes against all evidence and all studies on the topic and has no supporting evidence to back it up. ALL SWANS ARE WHITE.