The Grid That Reads Your MIND!!

Pick any four numbers from this grid — no two in the same row or column — and add them up. I already know your answer. And no matter which four you choose, it's always the same. In this video we do the trick, make it bigger, and then uncover the simple, beautiful idea hiding inside — the reason your "free" choice was never really free. You'll even learn to build your own version that forces any number you like. And there's a twist: even the most famous magic square in the world fails this trick. Can you work out which grids do work? Pause and try it along with me, and tell me what you find in the comments. 0:00 The trick 1:31 Try it yourself 2:15 A bigger grid (5×5) 3:28 The secret (addition table) 7:13 Build your own 7:48 Even Dürer fails 9:23 The question for you Where the numbers 15, 34, 65 come from — my Magic Square playlist: [   • The magic square problem  ] Subscribe for more puzzles that feel like magic. #maths #mathpuzzle #mathmagic #recreationalmaths #brainteaser