Principle of having it both ways? (5)
I believe the answer is:
I believe this is a double definition.
'principle' is the first definition.
(I've seen this before)
'having it both ways?' is the second definition.
'of' is the link.
(Other definitions for tenet that I've seen before include "It's believed" , "Teaching" , "Palindromic principle or belief" , "Belief held as true" , "Doctrine, dogma, belief" .)