8 
7 
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e f g 1 h Why it works
After 5.Be2! Bxf3 6.Bxf3 the d4-pawn looks abandoned — the queen already sits on d5, one square away. 6...Qxd4?? forgets what the recapture on f3 changed: the bishop now X-rays c6 through the queen's old square. 7.Bxc6+! removes the d4-queen's only defender with check — Black must attend to the king first — and 8.Qxd4 wins queen for bishop. A removal-of-the-guard so clean it belongs in a textbook: check, capture, resign.
Refutation
6...Qd7 (or 6...Qd6) steps off the firing line and admits the truth: d4 was never really hanging. Black is a bit passive after 7.c3 or 7.Be3 (engine −1.0) — the price of the early ...Nc6 blocking the c-pawn — but the game goes on. Before taking any 'free' central pawn, run the checklist: what does the recapturing piece defend, and what did my capture stop defending?