Jeremy Silman (born August 28, 1954) is an American International Master of chess. He has won the US Open, the American Open, and the National Open, and was the coach of the US junior national chess team. Silman has authored over 35 books, mostly on chess but also on casino gambling, and served as a chess consultant on the 2001 Harry Potter film Harry Potter and the Philosopher's Stone. He has given lessons to many top players of the game and has contributed to chess magazines such as New in Chess. Silman is known for his instructional books for lower-rated chess players. He has also authored many chess mentoring puzzles on the chess.com website.In his books, Silman evaluates positions according to the "imbalances", or differences, which exist in every position, and advocates that players plan their play according to these. A good plan according to Silman is one which highlights the positive imbalances in the position. The imbalances are, in rough descending order of importance according to Dana Mackenzie:superior minor piece, which refers to the relative strength of the knights and bishops;pawn structure;spatial control;material; in his Chess Life series The Art of Planning, Silman called this the most important imbalance because it had an impact on every phase of the game;control of open files, diagonals, and squares;development;initiative; Silman notes that this (along with superior development) is a dynamic imbalance that must be used quickly if the advantage is not to fade away.Silman was a regular contributor to Chess Life, writing educational columns for amateur players. In many cases he included games played by amateurs, pointing out the mistaken thought processes such players make. His annotations are known for the candor, and occasional harshness, for example The Amateur's Mind chastises a student with "This incoherent litany shows why he doesn't do well in tournaments". Silman has directed this harshness towards his own play as well, for example annotating the game Silman-Delaune, he wrote that having won material, he thought the game would win itself, and that "With this terrible mental attitude, White ceased to think, refused the draw offer, and coasted along mindlessly, making one awful move after another".