For artful deception, need a subject (5)
I believe the answer is:
topic
'a subject' is the definition.
('topic' can be a synonym of 'subject')
'for artful deception need' is the wordplay.
'for' becomes 'to' (eg both can mean 'in the opinion of').
'artful deception need' becomes 'pic' (I can't justify this - if you can you should give a lot more credence to this answer).
'to'+'pic'='TOPIC'
Can you help me to learn more?
(Other definitions for topic that I've seen before include "Subject (of a talk, etc)" , "one discussed" , "Subject (eg, of text)" , "That may be debatable" , "Issue (for discussion)" .)