It is human nature to ponder on the mechanism of things- that is how we got the wheel, agriculture, the vaccine for smallpox, the printing press and the transistor, to name a few inventions. This trait is beautifully put into words in Kurt Vonnegut’s 1963 novel Cat’s Cradle
Tiger got to hunt, bird got to fly; Man got to sit and wonder ‘why, why, why?’ Tiger got to sleep, bird got to land; Man got to tell himself he understand.
These lines beautifully capture the essence of humans- our never-ending quest for finding answers to questions. Mechanistic Interpretability tries to find answers to our questions on model internals and behaviour.