As well as the fact that sometimes entire new fields open up in very short periods of time -- for example, physicists thought at the end of the 19th century tha

As well as the fact that sometimes entire new fields open up in very short periods of time -- for example, physicists thought at the end of the 19th century that they were basically just tying up loose ends, when relativity and quantum mechanics burst on the scene (in a relatively short time span).