Darned if you aren't right, Lisa! Googled it: Sadow applied for a U.S. patent in 1970, and in 1972, he was granted the first successful patent on wheeled suitcases. Macy's sold the first suitcases in October 1970. Stable version came out in 1980.
I believe when it is time to invent the light bulb, it will be invented, not by just one person, but by more than one. If the Wright brothers had not produced the airplane, the French were right behind them with a controllable aircraft.
I don't know if there is such a thing as universal mind. They say "necessity is the mother of invention." I say laziness can be the mother of invention as well, hence wheels on a suitcase.