Word Choice – Principle Versus Principal

Corina’s question: “Can you please discuss when to use ‘principle’ versus ‘principal?’ ”

BizWritingTip response: I remember being taught that the person who runs the school was your pal; therefore, the person’s title was the principal.

But there are many other meanings for this word. As a noun, it can refer to the leading performer in a play or a concert, a sum of money (excluding interest or profit), or a person for whom another acts as an agent. As an adjective, it means chief or first in rank or importance.

Examples
The principal goal of the meeting is to obtain volunteers.
After the performance, there was a reception for the principals.
I can only pay the interest, not the principal on the loan.

“Principle,” on the other hand, refers to a fundamental truth or law, a personal code of conduct, or a primary element.

Examples
I refused to read the book on principle. (I didn’t read it because of my moral attitude.)
He has high principles.
The principles of physics dictate that you cannot travel faster than the speed of light.

Here’s another way to remember this. If you are talking about a rule (mental or otherwise), then use principle. Both words end in –le.