I don't think there's any convincing necessary - you're the paying customer aka the student. Talk to them openly about what you are changing from and what you're changing to.<br />
Also, think realistically about your "major" - if you can go the long haul for a doctorate in psych, you can make a great career for yourself. It requires patience, funds and time. <br />
There are also many majors that require psychology classes (aka, teaching) that may also be a suitable fit.... <br />
Best of luck! It's a gift simply knowing what you'd like to do - use the interview as an opportunity to explore realities.
explain why and give lots of reasons for the subject that you're interested in
Go forward. Change the course. They cant do it anything afterwards. Life decision. Best of luck. :)
That line about "not going to give up on my passion" seems pretty darned good to me.
Why an interview? Isn't how it works where I take classes