I agree that this feeling of being on the cusp of something big is ultimately just that, a feeling, and one should not try to be more specific about it. However, it seems to me that there is at least one type of situation where that feeling is grounded in fairly hard and verifiable facts, namely, when the idea in question is a scientific invention. Rudolf Diesel had a pretty good grasp of what the advantages of his engine were, and Tesla and Siemens knew pretty well why and how their AC power system was superior to Edison's DC. I'm a little irritated by the fact that this kind of scientific evidence for the value of an idea receives practically no attention at all in today's treatment of startup businesses, like the Lean Startup movement. Today, we ask the customers if they want AC or DC in their homes, and if the answer is DC, we pivot to that. Perhaps it would have been worth to stick with the AC idea a little longer, to fight for it, and to let its benefits sink in with people.