Leaving the base was the only rational thing to do.

This would be the rational, responsible and fair thing to do.

"They fall in love with a particular boat, and it's not a fully rational thing."

The rational thing is to do what makes you comfortable.

He nodded, suggesting she was doing the only rational thing.

Can't they see that this was the only rational thing to do?

The curfew, then, was not a rational thing for her.

A nonsense, but he's seen as a role model in things rational and responsible.

Every rational thing inside of him says "no" but his emotions are saying yes.

A little while ago, that would have been the rational thing to do.