Of Benjamin Franklin’s inventions, I would argue that the one that has had the most impact on the modern world is bifocal eyeglasses. These have been a great help to many people in our modern world.
In our modern world, bifocals are much more important than they were when Franklin was alive. In those days, there were many people who were not literate. There were not nearly as many things around to be read. There were not nearly as many jobs which required people to do a lot of reading as there are today. For these reasons, reading was not as important in those days as it is today.
In addition, people did not live as long in those days. Because people did not live as long, fewer people ended up needing bifocals. Those who did need them often did not need them for as long as people do today. This, too, meant that bifocals were less important in those days.
In today’s world, bifocals are very important. Many people work in jobs that revolve around reading. People have relatively long lives. These factors combine to make bifocals, which are very helpful for allowing older people to read, extremely impactful in our modern world.