I can't help but have the feeling that there is something simplistic and fundamentally flawed with the concept of productivity in this context. The assumption a

I can't help but have the feeling that there is something simplistic and fundamentally flawed with the concept of productivity in this context. The assumption appears to be that advances, like buses in the public transport system, should show up on a more or less regular basis. However that appears to ignore or misunderstand what all these scientists and engineers are actually doing - foraging. They are searching for new things in a multi-dimensional space with the added complication that traversing the area where ideas may be encountered gets increasingly more complex to navigate and relies on more people - either searchers or support staff or other searchers building the tools needed to do the searching, etc. etc. The apt (but somewhat stretched) analogy here is space travel. It's relatively simple to put up a high-altitude balloon - even school kids can do it now. Travel to the local planets - difficult but we've been doing it for a few years now. Sending probes to the next galaxy - not happening anytime soon. So why don't we ask the same questions of the aerospace industry? Probably because it's easier to see that getting from A to B and then to C takes a lot more effort and a lot more people and support infrastructure. Of course the other possibility is that advances are simply harder to find, not because we are looking in the wrong places or not looking hard enough but that there are limits to creativity in the way we think and so advances become a form of the infinite number of monkeys scenario where if you throw enough monkeys at the problem you will get the complete works of Shakespeare - eventually. I know this must be disappointing for the bean-counters that fund all this science but some problems are hard and barring the arrival of a generation of super-geniuses are going to stay hard unless we can find completely new ways of doing things - which is going to take a lot more effort.