Occlumency
The magical discipline of closing one's mind against Legilimency and other outside influence.
Occlumency is the practice of sealing one's mind against outside penetration and influence, and above all against Legilimency, the art of reading a mind from within. Harry Potter is taught it in Harry Potter and the Order of the Phoenix. Anyone who practises it is called an Occlumens. The discipline is ancient and obscure, dating back to medieval times, and it is reckoned difficult to learn. A skilled Occlumens keeps their thoughts and feelings from a Legilimens entirely, and can resist attempts to plant or steer them.
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