One quote for every 7 books:

The truth is a beautiful and terrible thing, and should therefore be treated with caution.-  The Philosopher's Stone-

“It is our choices, Harry, that show what we truly are, far more than our abilities.”-  Chamber of Secrets.

''Happiness can be found, even in the darkest of times, if one only remembers to turn on the light.'' - Prisoner of Azkaban.

''Numbing the pain for a while will make it worse when you finally feel it. The Goblet of Fire''

''The mind is not a book, to be opened at will and examined at leisure. Thoughts are not etched on the inside of skulls, to be perused by an invader. The mind is a complex and many-layered thing''. - Order of Phoenix.

''People find it far easier to forgive others for being wrong than being right.''-  Half Blood Prince.

''Where your treasure is, there will your heart be also.'' - Deathly Hallows.
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