Understood philosopher cutting works? (7)
I believe the answer is:
sawmill
'cutting works?' is the definition.
(works or factory that cuts wood)
'understood philosopher' is the wordplay.
'understood' becomes 'saw' ('see' can be a synonym of 'understand').
'philosopher' becomes 'mill' (John Stuart Mill).
'saw'+'mill'='SAWMILL'
(Other definitions for sawmill that I've seen before include "workplace that can produce deal" , "Log cutting plant" , "country establishment" , "Cutting workplace" , "Place where timber is cut into planks" .)