Editing Two Knights Defense (section)

{{Short description|Chess opening}}
{{Infobox chess opening
|openingname = Two Knights Defense
|image = {{Chess diagram
|
|
|rd|  |bd|qd|kd|bd|  |rd
|pd|pd|pd|pd|  |pd|pd|pd
|  |  |nd|  |  |nd|  | 
|  |  |  |  |pd|  |  | 
|  |  |bl|  |pl|  |  | 
|  |  |  |  |  |nl|  | 
|pl|pl|pl|pl|  |pl|pl|pl
|rl|nl|bl|ql|kl|  |  |rl
|
}}
|moves = 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6
|ECO = C55–C59
|birth = Late 16th century
|nameorigin =
|parentopening = [[Italian Game]]
|AKA = Prussian Defense<ref>Hooper & Whyld (1996), p. 324. ''Prussian Defence''.</ref>
|chessgid = 24146&move=4&moves=e4.e5.Nf3.Nc6.Bc4.Nf6
}}

The '''Two Knights Defense''' (also called the '''Prussian Defense''') is a [[chess opening]] that begins with the moves:
:1. [[b:Chess Opening Theory/1. e4|e4]] [[b:Chess Opening Theory/1. e4/1...e5|e5]]
:2. [[b:Chess Opening Theory/1. e4/1...e5/2. Nf3|Nf3]] [[b:Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6|Nc6]]
:3. [[b:Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4|Bc4]] [[b:Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...Nf6|Nf6]]

First recorded by [[Giulio Cesare Polerio]]<ref>{{cite book |author=Y. Estrin |title=The Two Knights Defence |publisher=Batsford |year=1983 |isbn=0-7134-3991-2}}</ref> (c. 1550 – c. 1610) in the late 16th century, this line of the [[Italian Game]] was extensively developed in the 19th century. Black's third move is a more aggressive defense than the [[Giuoco Piano]] ([[b:Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...Bc5|3...Bc5]]). Black allows White to attack his f7-pawn with 4.Ng5. If White does so, the game quickly takes on a tactical character: Black is practically forced to give up a pawn for the [[Initiative (chess)|initiative]]. The complications are such that [[David Bronstein]] suggested that the term "defense" does not fit, and that the name "Chigorin Counterattack" would be more appropriate.<ref name="Bronstein">{{cite book |last=Bronstein |first=David |author-link=David Bronstein |orig-year=1973 |title=200 Open Games |year=1991 |publisher=Dover |isbn=0-486-26857-8 |pages=60–61}}</ref> The Two Knights has been adopted as Black by many aggressive players including [[Mikhail Chigorin]] and [[Paul Keres]], and [[World Chess Championship|world champions]] [[Mikhail Tal]] and [[Boris Spassky]]. In modern [[Grandmaster (chess)|grandmaster]] play, 3.Bc4 is less common than [[Ruy Lopez|3.Bb5]], and the more solid 3...Bc5 is the most frequent reply, so the Two Knights Defense is infrequently seen. It remains popular with amateur players. The theory of this opening has been explored extensively in [[correspondence chess]] by players such as [[Hans Berliner]] and [[Yakov Estrin]].
{{AN chess|pos=toc}}