the fact or condition of being predisposed

a predisposition to think optimistically.

Medicine/Medical . tendency to a condition or quality, usually based on the combined effects of genetic and environmental factors.

noun

disinclination , unwillingness

noun

bent * , bias , choice , cup of tea * , dish * , disposition , druthers , flash , groove , leaning , likelihood , liking , option , partiality , penchant , potentiality , predilection , preference , proclivity , proneness , propensity , susceptibility , tendency , thing * , type , weakness , cast , squint , trend , turn , diathesis , inclination , willingness