subrational
adjective
sub·ra·tio·nal ˌsəb-ˈrash-nəl 
-ˈra-shə-nᵊl
variants or sub-rational
: being at a level below what is rational: such as
a
: existing or originating below the level of rational thought
subrational beliefs/motivations
Reason divides men; only subrational sentiment reliably unites them.
Clifford Orwin
Clifford Orwin b
: lacking the ability to reason
subrational creatures
Word History
First Known Use
1883, in the meaning defined above