d 3 ▁ ▁The ▁quiet ▁move ▁ 4 . d 3 ▁trans poses ▁into ▁the ▁Gi u oco ▁P ian iss imo ▁if ▁Black ▁respond s ▁ 4 ... B c 5 , ▁but ▁there ▁are ▁also ▁independent ▁variations ▁after ▁ 4 ... Be 7 ▁or ▁ 4 ... h 6 . ▁White ▁tries ▁to ▁avoid ▁the ▁tact ical ▁batt les ▁that ▁are ▁common ▁in ▁other ▁lines ▁of ▁the ▁Two ▁Kn ights ▁and ▁to ▁enter ▁a ▁more ▁position al ▁game . ▁The ▁resulting ▁positions ▁take ▁on ▁some ▁characteristics ▁of ▁the ▁R uy ▁L ope z ▁if ▁White ▁plays ▁c 3 ▁and ▁retre ats ▁the ▁bishop ▁to ▁c 2 ▁via ▁B c 4 – b 3 – c 2 . ▁This ▁move ▁became ▁popular ▁in ▁the ▁ 1 9 8 0 s ▁and ▁has ▁been ▁used ▁by ▁John ▁N unn ▁and ▁others . ▁Black ▁can ▁conf ound ▁White ' s ▁attempt ▁to ▁avoid ▁tact ical ▁play ▁with ▁ 4 ... d 5 ! ? ▁This ▁move ▁is ▁rarely ▁played ▁as ▁opening ▁theory ▁does ▁not ▁appro ve , ▁but ▁Jan ▁Pi ński ▁suggests ▁that ▁it ▁is ▁better ▁than ▁is ▁commonly ▁believed . ▁In ▁practice ▁after ▁ 5 . ex d 5 ▁White ▁still ▁has ▁strong ▁winning ▁ch ances . ▁ ▁Four ▁Kn ights ▁Vari ation : ▁ 4 . N c 3 ▁ ▁The ▁attempt ▁to ▁defend ▁the ▁pa wn ▁with ▁ 4 . N c 3 ▁does ▁not ▁work ▁well ▁since ▁Black ▁can ▁take ▁the ▁pa wn ▁anyway ▁and ▁use ▁a ▁fork ▁trick ▁to