Hold your opinions with an open hand. A clenched fist can’t pick up anything new.

Defending a position and understanding one are different activities, and the first tends to crowd out the second. Once you have committed out loud, every new fact gets sorted into threat or ammunition instead of information. Loosening your grip does not make you a pushover; it keeps your hands free. People who change their minds well are not weaker, only more current.

Take something you are sure about and find the strongest version of the other side, stated by someone who actually believes it. You do not have to move. You only have to be able to say it fairly.