If you don't know how to do it, you don't know how to do it on a computer

I once had a boss tell me, after I showed some results from a horrendously complex computer model that neither he or I understood, that "If you don't know how to do it, you don't know how to do it on a computer".

I would much rather see the fate of the world's economy rest on a model that somebody understood, rather than some ginormous simulation with zillions of parameters that nobody understands.