If you give people a firm opinion, you run the risk of being wrong.

I just happen to have firm opinions on what my job's all about.

There were few subjects on which he did not have firm opinions.

All said they did not have firm opinions on the death penalty.

Me, I don't have a firm opinion on the matter.

They are proud of their culture, and they've got firm opinions.

I haven't read enough Williams to have any firm opinion of his work, myself.

I'm of a firm opinion she was poorly represented today.

Their reviewing physician did press me for a more firm opinion.

It's my firm opinion that there is something very unusual in this doctor's story.