There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.
– Hamlet (1.5.167-8), Hamlet to Horatio
The mere fact that a man fails to make sense to ME does not mean that he fails to make sense AT ALL.
There is a distinction between the irrational and the non-rational.
When a person makes irrational decisions, it means they are reasoning about concepts in an inconsistent manner or contradicting themselves through a violation of their own standards, principles, and core values.
When a person makes non-rational decisions, it means they are allowing their choices to be guided by their instincts, intuition, feelings, and tastes.
Sometimes the latter conflicts with the former, but not as a matter of strict necessity.
The irrational refers to that which goes against logic.
The non-rational refers to that which goes beyond logic.
True rationality recognizes that human beings are multidimensional creatures and that our behavioral choices involve a variety of influences. Good logic understands that there are thoughts worth having, feelings worth feeling, and decisions worth making that simply do not arise as a consequence of conceptual analysis and syllogistic reasoning.