As part of the Theory of Inventive Problem Solving(TRIZ), Genrich Altshuller, by studying patented inventions, came up with five levels of inventiveness, as pictured. I think that he called it the Pyramid of Inventiveness. The idea there being that if every level represents a standard deviation, the distribution is similar to a normal curve. As you can see, however, there are more inventions in level 2 than level 1. The missing inventions* from level 1 often go unpatented due to the following: being of limited usefulness; being treated as suggestions rather than inventions; failure to meet patent requirements.
*
I have been looking for a term for missing data in a population. For example, not every country plays rugby or cricket. When you look at the top 100 players in the world, there are people who should be in this list but are not because of a lack of opportunities, or maybe just more lucrative ones like MLB or NFL.
The following summarise in general terms the different
levels:
