Religious authorities are “unanimous” that “it is a mitzvah [commandment] to drink, and drink to excess, on Purim”, says Jewish website Chabad.
Exactly how drunk one should aim to get has been a matter of rabbinical debate for centuries, although 4th century rabbi Rava held that one should drink “until he does not know the difference between ‘cursed be Haman’ and ‘blessed be Mordechai’”.