Traditional 3-3 Invasion Joseki
Return to parent joseki article: 4-4 Point 3-3 Invasion, Hane
The 4-4 Point 3-3 Invasion, Traditional Joseki is a classic invasion of the 4-4 point that was historically the mainline variation.
Discussion
Historically, invading the 3–3 point early in the game was considered bad because it was believed that this variation gave the non-invading player superior outward influence. However, AlphaGo showed that this assessment was incorrect and the outward influence was being overvalued by human players (i.e. the outward influence and inside territory are more balanced than previously thought). Several, new standard joseki were innovated by AlphaGo (and by subsequent professional play) and have since become extremely popular in both professional and amateur games. Responding to a 4-4 opening with a 3–3 invasion early in the game is now considered acceptable.