והמשתכר אל ישתכר יותר משתות (בבא בתרא 90A)
"One who gets drunk may not get drunk past a sixth."
I have seen four shittos to explain this ruling which is brought l'halacha in O"C Siman 683.
Panim Chalashos (OC 883:2) says that one who reaches ad d'lo yada and wishes to continue drinking must make each drink 1/6 the size of the previous one until he asymptotically approaches either zero or the inability to say asymptotically whichever comes first.
Ta"m (Turei mashke) ad loc points out that Ta'us sofrim records שתות as a copyist error and that the correct girsa is שטות i.e. one should not drink past the point when he begins to act like an idiot. If he does, then chazrah hamekach and the owner of the liquor store is permitted to take back his wine.
Magen Avraham challenges the Ta"M and asks how he can pasken based on this obscure rishon and completely dismiss the longstanding minhag yisroel to drink far past that point. The original girsa stands but shtus does not mean 1/6 of the previous drink but 1/6 more so that if you start with a 6 ounce glass, your second drink should be 7 ounces and so on.
משנה בירה paskens like Magen Avraham but adds that a baal nefesh should add a sixth mil'bar.
How are we machriah l'mayseh?
