I was at a public lecture and later saw photos of it. In one photo I held my index finger across my lips. A guy sitting before me, whose face I couldn’t see at the time, did the exact same gesture, and the resulting photo looks pretty funny, as if we’re all consciously posing to signal that we’re thinking real hard.
There are other poses of this sort, the thinking monkey meme, Rodin’s Thinker statue… even the sidebar of this very sub has a picture of a lemur whom we recognise as “thinking” because it has its hand on its mouth.
Are these gestures just culturally conditioned? But regardless of whether they’re just cultural or universal – why do they exist?
Yes, it’s cultural. Using your hands to think in general is natural, just like head movements - but the actual movements we use are cultural
There’s some natural shaping to the movements, such as tilting your head to signal you’re paying close attention - tilting your head can help you hear more clearly. In the same way, covering your lips in some way signals you’re not trying to speak
But ultimately, in another timeline everyone would be bobbing their head from side to side to signal consideration… It’s shaped by instinct to some extent, but dominated by culture