But by that line of reasoning, shouldn't we never hit dead ends in AI research at all -- why has AI progress been so difficult, then? Wouldn't any field of rese

But by that line of reasoning, shouldn't we never hit dead ends in AI research at all -- why has AI progress been so difficult, then? Wouldn't any field of research with many dimensions of variation never get stuck on its path towards its ultimate goals, ever? Couldn't different objective functions be structurally more difficult than others to optimize? No matter how high-dimensional the search-space, trying to create a gaming laptop in the middle ages would have been a pretty frustrating experience.