It shows that the thinkers were driven by curiosity and belief in reason which they used in order to find causes for events and explore the nature of the universe so as to find out the place of people in it.
This reflects the advances of Greek society. They realised that in order to evolve as society and improve, they needed better rules, system and leader able to apply those changes. Also, liberty and freedom was understood by the Greeks us a essence of life, the difference between animals and humans.
So, a greater society was a free society, and that could only be achieved through a improved system.
