Warning: The following answer contains elements of actual Torah and is not meant to be taken entirely in jest.
It says in T'hillim (19:9): פִּקּוּדֵי יְהוָה יְשָׁרִים, מְשַׂמְּחֵי-לֵב. The Radak comments that Torah gladdens the heart, namely the intellect:
הם משמחי לב, כי החכם ישמח על שכלו. וכאשר יגבר על הגוף וינהגהו בדרכי השכל, אין שמחה בעולם כשמחה ההיא, והיא שמחת הנפש. לפיכך אמר: משמחי לב, ולא אמר משמחי האדם, כי האדם ישמח לתאות העולם, אבל השכל, והוא הלב, לא ישמח כי אם בדרכי שכל
Yet, we see from T'hillim (104:15) that wine gladdens the heart, and the reference here does not seem to be to the intellect: וְיַיִן יְשַׂמַּח לְבַב אֱנוֹשׁ.
What's the difference? The mishna in B'rachos (9:5) expounds: בכל לבבך בשני יצריך ביצר טוב וביצר רע. Thus we see that לְבַב indicates that wine allows one to gladden the totality of their being, including the yetzer hatov and the yetzer hara.
The gemara (M'gillah 7b) writes that on Purim one should drink festively: מיחייב איניש לבסומי בפוריא עד דלא ידע בין ארור המן לברוך מרדכי. However, because of the unfortunate incident recorded immediately after this, many rishonim and acharonim follow the Orchos Chaim and rule we don't have to get sooooo drunk. Still, they write, one should drink יותר מלימודו, more than his studies.
Why does the drinking have to exceed the learning? The rest of the year, we serve HaShem with joy by achieving שמחת הנפש, with our יצר טוב. However, on Purim we fulfill עבדו את השם בשמחה in the manner of לאהבה את השם א-להכם ולעבדו בכל לבבכם , with the entirety of our being. Why is Purim a special opportunity for this?
In the time of the Purim story, the Jews attended the feast of Achashveirosh. The feast was devoted to celebrating the ruins of the Jewish Temple and degrading its holy items. Achashveirosh himself brazenly wore the priestly vestments. The Jews should have sensed with the totality of their being that something was amiss; the celebration of Achashveirosh should have disturbed a Jew to his very core. Instead, what was the focus? The fact that technical halachos about the food at the seudah were observed (Megillah 12a). For this reason, that generation of Jews was nearly destroyed (ibid.).
In those times, the Jews corrupted their Torah learning by using it to justify gladdening themselves in a blasphemous celebration. We rectify that error by drinking festively more than we study; we allow the totality of ourselves to emerge free from the restraints of the intellect and joyously serve HaShem with שמחה, with all our heart, בכל לבבנו בשני יצרינו.