They all looked at him as if he'd gone out of his mind.

How am I going to get you out of my mind?

I could not get his face out of my mind.

I think you must have gone out of your mind.

One thing at a time or he'd go out of his mind.

I tried to force the idea out of my mind.

For the first few days I was out of my mind.

He could not get her out of his mind, though.

He tried to put the thought out of his mind.

As always, the first step is to keep knowledge out of his mind.