Thus, cases for philosopher (8)
I believe the answer is:
socrates
'philosopher' is the definition.
(I've seen this before)
'thus cases' is the wordplay.
'thus' becomes 'so' ('so' can be a synonym of 'thus').
'cases' becomes 'crates' (crating is a kind of casing).
'so'+'crates'='SOCRATES'
'for' is the link.
(Other definitions for socrates that I've seen before include "sage from Greece" , "Coarsest sort of Greek philosopher" , "Gk. philosopher, took hemlock" , "Plato's teacher, d. 399 BC" , "Hemlocked philosopher" .)