let (one's) heart rule (one's) head(redirected from let her heart rule her head)
let (one's) heart rule (one's) head
To do something based on one's own personal desires rather than for pragmatic or practical reasons. I couldn't believe it when I heard he'd bought a sports car, but then he has always been one to let his heart rule his head. I think she knows that a relationship with him will eventually end in tears, but she's letting her heart rule her head.