People use 'philopsophical' in a number of ways/. The first clause could mean that there is a strong inclination among philosophers. But 'philosophical' is often used in a more general sense, to do with attitudes: 'Sometimes you just have to take the philosophical view, and roll with the punches.' (This usage is deplored by some people, but the usage is so common that I think they just have to live with it!)
The Age of Enlightenment - Wikipedia, the free encyclopedia is a recognized period/movement, also known as 'The Age of Reason'. At this time, philosophers started arguing that previously-held notions of destiny and fate were wrong - that things happened because people did things that caused them ('the causal role of independent, self-reliant individuals in shaping events.')
PS In this context, I'm pretty sure the 'philosophical' is referring to a tendency among people writing in the context of philosophy.