The Greatest Regrets of mankind, according to me, should be as follows (in descending order):
1) The development of Intellect
2) The production of fire.
4) Discovery of electricity and Invention of Engine
5) The Protestantism
6) Definition of Freedom in America
7) The dropping of the atom bomb
8) The spread of pornographic industry
9) The American use of energy and resources
10) The growth of Chinese economy
11) The death of Mahatma Gandhi
12) The invention of JCBs and the electric wood saw.
13) The medicinal science and healthcare industry.
14) The systems of Capitalism and Communism
15) The world wars
16) The rise of terrorism
17) The swiss bank
18) The invention of the Gun
19) The growth of defence industry
20) The Nazi and Rwanda genocide