To bring that back into the tech/business world: My personal rule for being an expert/consultant is to be very willing to say "I don't know, but I can find tha

To bring that back into the tech/business world: My personal rule for being an expert/consultant is to be very willing to say "I don't know, but I can find that out for you", and define that as my real expertise: know how to find out things. Technology stacks, programming languages, all of those things come and go. The skill to pick up whatever is needed is long-term better.