* Philosopher took Spinoza on about conclusions (4)
I believe the answer is:
edge
'philosopher' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for edge that I've seen before include "Guitarist with U2" , "Margin, outside limit" , "Move slowly" , "Upper hand" , "Line where soething begins or ends" .)