Philosophy is a Tier Three technology that can be researched after Meditation. It was released in the "Power" Update.
The Philosophy tech unlocks the Mind Bender, a Unit that can heal your units and convert enemy units to your side.
It also unlocks the Genius Task and a literacy bonus , which reduces the cost of all Technologies by 20%.
The following text will be displayed at the bottom of the research screen once Philosophy has been researched:
Literacy reduces the price of all technologies by 20%!
(Note: The tech costs will be rounded up.)
While in beta, it used to unlock the Library, a building that decreased the costs of technologies, but was scrapped and replaced by the Literacy Bonus.
The icon for the Literacy Bonus