Philosopher needs help to carry box (8)
I believe the answer is:
socrates
'philosopher' is the definition.
(Socrates is an example)
'help to carry box' is the wordplay.
'help' becomes 'SOS' (emergency abbreviation SOS).
'to carry' indicates putting letters inside.
'box' becomes 'crate' (crate is a kind of box).
'sos' placed around 'crate' is 'SOCRATES'.
'needs' is the link.
(Other definitions for socrates that I've seen before include "Plato's teacher, d. 399 BC" , "Coarsest (anag) - philosopher" , "sage from Greece" , "old question-master?" , "Deep thinker" .)