There are probably six levels of above-average intellectual talent, each level starting at a new standard deviation above the mean.
Sigma 1
- Skills: is able to independently acquire knowledge from books.
- Typical Real-World Achievement: university degree in one of the "softer" branches of science such as sociology, psychology or political science.
- Rarity: 1 in 6
Sigma 2
- Skills: is able to solve problems by thinking.
- Typical Real-World Achievement: university degree in "hard science", such as mathematics, computer science, engineering, physics, chemistry, medicine or philosophy.
- Rarity: 1 in 44
Sigma 3
- Skills: is able to devise experiments from which new insights can be gained.
- Typical Real-World Achievement: professorship; most Nobel Laureates fall in this category.
- Rarity: 1 in 741
Sigma 4
- Skills: is able to write theoretical works with original thought processes from which new insights can be gained.
- Typical Real-World Achievement: being acknowledged as a "true genius", like Einstein.
- Rarity: 1 in 31,560
Sigma 5
- Skills: is probably able to establish a whole new branch of science alone.
- Typical Real-World Achievement: being acknowledged as a "true genius", like Einstein, or being considered a complete nerd and shunned by society.
- Rarity: 1 in 3,483,046
Sigma 6
- Skills: is probably able to develop a logically coherent theory about how the world works ("Theory of Everything").
- Typical Real-World Achievement: being acknowledged as a "true genius", like Einstein, or being considered a complete nerd and shunned by society.
- Rarity: 1 in 1,009,976,678