Anybody on earth should be benevolent (6)
I believe the answer is:
humane
'benevolent' is the definition.
(I've seen this in another clue)
'anybody on earth' is the wordplay.
'anybody' becomes 'hue' (I am not sure about this - if you are sure you should believe this answer much more).
'on' indicates putting letters inside (as in clothing 'on' a person).
'earth' becomes 'Man' (Man is an example).
'hue' enclosing 'man' is 'HUMANE'.
'should be' acts as a link.
Can you help me to learn more?
(Other definitions for humane that I've seen before include "Kind and liberal" , "Kind-hearted and compassionate" , "Benign - kind" , "Kind and sympathetic" , "Inflicting minimal pain" .)