The history of microscopes is surprisingly only about 400 years old. Surprisingly, because one has to bear in mind that all knowledge about microorganisms and the mechanisms of the diseases they cause can only be as old — but in fact it is much younger. All pathogens such as bacteria only became visible to humans under the microscope.
Previously, one could only assume how diseases were transmitted from one person to another. In particular, this made many doctors aware of the relevance of hand washing, as it had previously been largely unclear why doctors could infect other patients simply by touching the diseases of previous patients. The London Academy of Sciences initially had little faith in the depictions of van Leeuwenhoek, who carried out one of the first traditional studies of microscopically small creatures.
Perhaps it was even more likely that the hard-working and wealthy merchant, who had always been known as a somewhat strange full-time professional, had now completely lost his mind. It was only when the Academy’s delegate could take an independent look into a completely new world that Leeuwenhoek received the honour he deserved.
In particular, the microscope has established the concept of cells and thus a large part of research and ideas in modern biology.
In particular, it led to the conclusion that every form of life on Earth is made up of cells and that the cell is thus a “smallest unit of life”. It is hard to imagine a world in which as little is known about the microscopic origins of life and the laws of nature as before the invention of microscopes. After all, it is responsible for the development of microbiology as a whole and has also significantly influenced the notions of life within biology.