Umm... beg to differ. Anybody who invented anything pretty much had a whole bunch of folks who came before to ask questions of. In the case of David Bushnell, who built the Turtle, he consulted with Benjamin Franklin among others at Yale, his college. Orville and Wilbur Wright are credited with inventing the airplane, but there were plenty of others who could make the same claim. General Hua Mulan herself may well have used kites to aid in her logistics efforts as early as the seventh century. Who "invented" those kites? I dunno, but you can bet that if anyone knew, it was Orville and Wilbur.
Edison is widely regarded as a great inventor.... but he probably adapted (stole) as many things from other inventors as he "invented" himself. Inventors almost always stand on a tower of giants who came before them.
The first step in the invention process is a random idea. If it goes any further than that, the next step is research. There is no need, for example, to re-invent the wheel. You might improve upon it, but the basic idea is sound and was invented by some stone-age man perhaps inspired by watching something round roll down a hill. The first thing he did, was likely to sit down at his hearth, sidle up to his much smarter wife and say something on the order of "Honey, you ever heard of anybody putting logs under something heavy in order to move it easier?" She likely said something like, "Ya, sorta. The people on the island where I grew up used logs to get double-hulled canoes to the water after they were built." "What kind of trees did they get the logs from?" And soon enough, Michelin started making tires.
