Which is an uncomfortable thought. If they were just like us, then they had to work very hard to do what they did. To quote one of my professors: "scientific g

Which is an uncomfortable thought. If they were just like us, then they had to work very hard to do what they did. To quote one of my professors: "scientific greatness requires three things: some intelligence, hard work and some luck". If Einstein hadn't invented the theory of relativity, someone else would have. The relevant equations had already been around for years, waiting for a proper physical interpretation: the time was ripe for it. There probably were a number of authors as prolific and proficient as Shakespeare, that have nevertheless vanished in obscurity, because Shakespeare just happened to get and keep the attention. From not being succesful you can never conclude you have not been working hard enough: someone else may have gotten lucky.