For so many of us, Harry Potter defined the highs and lows of childhood. Despite the series being stamped as "young adult" fiction, J.K. Rowling's magnum opus has stuck with us. Ever since we met Harry on that fateful Halloween night, we were students. Twenty years later, we still are. These are 13 lessons that the Harry Potter series taught us. Beware of spoilers! Seriously, though, how have you not read these books?

1. Never lower your standards.

Sure, Harry kills Voldemort in the end, but he never uses the killing curse. By staying true in the final moments of the series, Rowling taught us that we must never resort to evil to conquer evil.

2. Sometimes "correct" and "right" aren't the same thing.

Even though Harry was only supposed to save Ron, he knew better than to leave Gabrielle Delacour.

3. Consent.

If "Yes Means Yes" had a mascot, it would be a hippogriff.

4. Winning isn't important.

Neither are winnings. True Potterheads will remember that Harry gave his Triwizard Tournament prize money to the Weasley twins.

5. Evil comes in every flavor.

Voldemort was bad, but he had nothing on Dolores Umbridge. Also, don't get me started on Gilderoy Lockhart.

6. Sometimes just being there is enough.

When there's nothing you can do to help, the least you can do is not cause any more hurt.

7. "It takes a great deal of bravery to stand up to our enemies, but just as much to stand up to our friends."

We should all hope to be as brave as Neville.

8. Consider others' perspectives before making judgments.

Sirius. Snape. Merope Gaunt. Dumbledore. The list goes on.

9. Love is the only appropriate response to hatred.

The best magic that we have.

10. Those who love the least, need it the most.

Even the bad guys have a backstory.

11. Always be yourself.

Gnargles!

12. You're stronger than you think.

"Whether you think you can, or you think you can't, you're right."

13. The ones that love us never really leave us.

Always.