The doubter is a true man of science; he doubts only himself
but he believes in science

Some of the best inventions have been mere innovations on previous inventions that existed. Many inventions have been discovered in response to a need in society or within business. For example, Eli Whitney invented the cotton gin in order to improve business and speed up production. Innovations like this one have been going on for hundreds of years. Even early man was determined to come up with innovations of his own, such as the wheel which still plays a vital role in our lives today.