He was a very able mathematician and developed many theories. The question needs to be more specific. Which theory are you referring to?
an orchid mantis does or does not help mankind. which means that it doesn't help mankind but its not bad for mankind either
entertainig mankind
shelter
There are a lot of things that could be done to help mankind. The invention of airplanes was a great achievement that has changed mankind.
The plant help mankind by purifying the air by absorbing CO2 and releasing O2 during synthesis of organic compounds used by entire animal kingdom including mankind.
she suck
made the first flag
nothing
They helped by making wok easier
They didn't help with atomic theory, they created it.
philarthropy
A cure to HIV