As a kid, my coach, an International Master, was repeating "if you have three pieces or more in the attack you can sacrifice without thinking!"
However, don't take this rule too literally!
- Chess is a concrete game and we should not follow a rule "without thinking". However, I believe that chess is guided by some rules and general principles.
- We can redefine the rule of "Three Pieces in the Attack" as "Play more aggressively in the attack" in a context where the number of pieces attacking exceeds the number of pieces defending.
My question is: by searching on the Internet, I could see this rule from time to time but I could not find its origin. Who devised this rule? How old is it?
I found a cute example here to illustrate this rule. White plays and checkmates a strong GM!
[title "Juarez Flores, C - Lputian, S, Manilla 1990"] [fen "r6r/p4ppp/2p1b3/4R3/1kpR1N2/6P1/P1P2P1P/2K5 w - - 0 1"] 1.
I cover the solution for those who want to search:
1. a3! Kxa3 (1...Kc3 2. Ne2#) (1...Ka4 2.Nxe6 fxe6 3.Rxc4+ Kxa3 4.Ra5#) 2.Nxe6 Kb4 (2...fxe6 3.Rxc4 c5 4.Re3 Ka2 5. Ra4#) 3.Rc5 fxe6 4.Rdxc4 Ka3 5.Ra5#
The Greek Gift is another illustration of this rule because the
Nf3 and the
Qd1 coordinate to attack (the
Bc1 and the
Rh1 can also join the party)
[title "Greco 1792"] [fen "r1bq1rk1/ppppbppp/2n1p3/3nP3/3P3P/3B1N2/PPP2PP1/RNBQK2R w KQ - 1 1"] 1. Bxh7! Kxh7 2.Ng5 Kg8 3.Qh5 Bxg5 4.hxg5 f5 5.g6+-