Quoted: C. S. Lewis on Philosophy

To be ignorant and simple now – not to be able to meet the enemies on their own ground – would be to throw down our weapons, and betray our uneducated brethren who have, under God, no defense but us against the intellectual attacks of the heathen. Good philosophy must exist, if for no other reason, because bad philosophy needs to be answered.

C. S. Lewis, The Weight of Glory p. 50