[xvilka]

My small experience with being burned by hot or acidic liquid tells me exactly the opposite.

[Chris2048]

The anecdote is specific to frogs (and animals with similar sensory systems), and specific to boiling by increasing the temperature in small increments.

It's also a myth: https://en.wikipedia.org/wiki/Boiling_frog

Interesting that early experiments involved removing the frogs brain as well.