The New York Times | September 8, 2022
"Principal investigator reveals breakthrough in cancer research."
Principal vs. Principle
The '30 Seconds' Difference At A Glance
'Principal' means main or most important, and can also refer to the head of a school or organisation. 'Principle' means a fundamental truth, law, or standard.
The principal reason for the change was to uphold our principles of fair treatment.
A Deeper Look
'Principal' is used in two main ways: it means 'main' or 'most important', and it can also be the person in charge (especially at a school).
Cost was the principal factor in our decision.
The principal called an assembly to discuss the new rules.
'Principle' refers to important rules, beliefs, or ideas that guide how we think or behave.
It's against my principles to lie, even about small things.
The basic principles of physics apply to everything around us.
Common Usage Patterns
Principal
Common phrases: principal actor, principal investment, principal office, principal character, principal investigator
Principle
Common phrases: moral principles, basic principles, in principle, guiding principles, first principles
Key Patterns
'Principal' often appears before nouns it modifies or in job titles. 'Principle' typically appears in phrases about rules or beliefs.
What Teachers Say
"Remember that the school principal is your 'pal' - that's how I help students remember which spelling refers to a person."
-- Margaret, Vancouver
"In academic writing, students often discuss scientific principles. Just remember - if you're talking about rules or theories, it ends in 'le'."
-- Peter, Melbourne
"When reviewing financial documents, watch for 'principal amount' - it's one of the most common contexts where this word appears."
-- Sarah, Dublin
From The Headlines
The Telegraph | March 15, 2017
"Supreme Court ruling establishes new principles for online privacy."
Financial Times | June 22, 2012
"Banks agree to freeze principal payments on Greek debt."
Test Yourself!
1. The _______ of the high school called a meeting.
2. The company operates on the _______ of sustainable development.
3. The _______ amount of the loan must be repaid according to basic banking _______.
