Thomas Edison

Through all the years of experimenting and research, I never once made a discovery. I start where the last man left off. … All my work was deductive, and the results I achieved were those of invention pure and simple. Thomas Alva Edison (1847-1931), "The Wizard of Menlo Park", was an ingenious American inventor who was not particularly kind towards his rivals. In fact, he was pretty much an all-around jerk and asshole.

Inventions and patents
I came from Paris in the Spring of 1884, and was brought in intimate contact with him [Thomas Edison]. We experimented day and night, holidays not excepted. His existence was made up of alternate periods of work and sleep in the laboratory. He had no hobby, cared for no sport or amusement of any kind and lived in utter disregard of the most elementary rules of hygiene. There can be no doubt that, if he had not married later a woman of exceptional intelligence, who made it the one object of her life to preserve him, he would have died many years ago from consequences of sheer neglect. So great and uncontrollable was his passion for work. Apart from the phonograph, most of his inventions were improvements and adaptations of existing products, although this should not detract from the fact that he brought, for instance, the incandescent light bulb from being a laboratory device to commercial viability.

Edison's major rivals, during the late 19th century, were George Westinghouse and Nikola Tesla, who had once been an associate of Edison. In the so-called "War of Currents", Edison favored using "Direct Current" or "DC"-based power systems, arguing that DC power was safer than the more powerful "Alternating Current" or "AC" power systems which Westinghouse and Tesla were developing. Ultimately AC power came to be used much more widely, though Edison remains a more famous figure than his adversaries, due to his inventions and his business successes.

He claimed opposition to violence, stating;

According to a quote of disputed authenticity, Edison's philosophy of nonviolence extended to animals as well, about which he allegedly stated:

These two quotes seem to be outright lies as Edison promoted use of the electric chair. However, he never electrocuted an elephant publicly and in fact "Topsy" was killed by a circus for reasons wholly unrelated to Edison. While already obviously unrelated to the war of currents as it happened in 1903, approximately a decade after that conflict concluded, the only relationship the incident has with Edison is that his company's filmstock was used to record it. There was, however, the unfortunate bit that in his effort to convince people of the danger of AC he killed a number of animals...so maybe the consideration for living beings didn't really apply when his profits from electricity generation were at stake.

On religion
Edison has been accused of being an atheist based on some of his remarks, though it is almost certain that he was either an agnostic or most likely a deist. While he did make statements regarding religion such as these:

And while he also did not believe in an eternal soul or an afterlife:

It is also clear that he believed in a supreme being of some kind, which essentially lands him in the deist camp:

Final words and death
His final words are often taken by certain people with certain beliefs as a sign that he had a vision of the next world:

These have sometimes been reported as his last words, but were actually spoken several days before his death, as he awoke from a nap, gazing upwards, as reported by his physician Dr. Hubert S. Howe.

In an ironic finale, Edison's wife signaled his death to the press by turning a light on, not off, in a window of the house.