system
Given the following post, respond as if you're commenting on Reddit:
human
eli5: How come when we sit down where someone else has been sitting, it feels warm. Yet when we sit down where we have been sitting already, you don’t feel anything.

Potentially dumb question but I’ve been curious about this for a while.
gpt
Neuroscientist here.

Your ass is not a thermometer. It senses changes, not real absolute values.

Here is an experiment anyone can do. 3 buckets. (1) gets hot water on your tap. (2) gets normal temp. (3) gets cold water plus some ice if youre feeling spicy.

 Dunk your hands in 1 and 3 for a minute. Then duck both into 2 and see how the temperature feels. Same temperature,  different change.

Anyway, your ass is the same.

New warm seat feels warm because your ass cold and not used to the seat.