As a rule, drunkenness is disgraceful and liable to lead to trouble, as is clear throughout biblical and rabbinic literature. However, we cannot ignore the positive aspects of drinking, as it can cheer people up and help them relax.
On Purim in particular, when a miraculous salvation came about through events that involved drinking (Ahasuerus' drink-laden feasts), it is appropriate to give expression to drinking’s positive aspects. Additionally, on Purim, it becomes clear that everything God does to the Jewish people is for the best. Even terrible edicts can ultimately benefit us. When we have this complete faith, boundless joy permeates all aspects of our lives.