I love reading the comments when you post topics like this, because you can have one comment that is astute, rigorous, and based on sound logic and empirical knowledge, literally adjacent to another comment that reads like Deepak Chopra after a massive bong-rip.

The rational comments are fun, but the quantum-woo is even better.

On the substance, I'm fairly certain that I have absolutely no ability to decide if math is a "real" thing or an illusion.

I'm not going to be the one to say with any level of certainty that I understand math better than realists likes Godel or Quine, or formalists like Hilbert or Tarski.

The only thing I'm certain about is that people who claim to be certain about the answer to this may not be giving a fair hearing to the theories on both sides.