What simulations often lack is any clear validation against reality. The true test of a simulation is it's ability to predict the behaviour of a real system, it

What simulations often lack is any clear validation against reality. The true test of a simulation is it's ability to predict the behaviour of a real system, it's not enough to say "their construction has some similar features so it's probably ok". Weather simulations are generally reasonable, though limited in this regard. Other scientific simulations tend to be a little more hazy, the main aim of course being to produce a publication. You said "Hypothesis are proved or disproved, science advances, and we know that much more about how such complex systems indeed work". Could you provide some examples? In my experience I've rarely seen simulations have have proved or disproved hypothesis. This is an honest question, if you have some references to significant results from simulation I'd be interested in reading them.