They don't have to identify it and they don't have to know it's missing. My whole point is that the breakthroughs will happen in some other technology tree, and they will most likely occur in the context of some more mundane, profit-seeking commercial endeavors, in much the same way that advances in metallurgy and machine tool technology enabled the steam engine although the basic principle and some crude prototypes were already available since classical antiquity. What's been happening since the 1950s in robotics (I am not talking Toyota car factory robotics) is simply a misallocation of taxpayer's capital and hurts science and technological advancement since it fails to allocate research capital in the way most likely to lead to sustainable, economically exploitable breakthroughs. Of course all that pales in comparison to money wasted in social "sciences" etc.