voice of reason
voice of experience

Was he at last about to listen to the voice of reason?

This had gone far enough - a voice of reason was needed here.

It takes some effort to be a voice of reason.

He was not certain if love could hear the voice of reason.

Do you see him as a voice of experience and reason?

Within the office, Mary is often the voice of reason.

That way, they wouldn't have to be the voice of reason all by themselves.

She was clearly the voice of reason in the family, thank God.

If it is possible, let the voice of reason be heard.

She is often the voice of reason on the show.