The microscope provided the technology to explore the world of microscopic organisms. Before the invention of the microscope, many people believed in spontaneous generation—the emergence of life spontaneously from non-living matter. With the invention of the microscope, scientists were able to show many living organisms that could not be seen with the naked eye. The microscope also showed details of cells and, therefore, led to the development of cell theory.

Spontaneous generation thrived until the nineteenth century. In the seventeenth and eighteenth centuries, scientists performed a number of experiments that disproved the theory of spontaneous generation; however, spontaneous generation continued to be accepted.

Read Pages 247-249, 251-252 for detailed information regarding the development of the cell theory