At the very moment that Alceste is decrying the faithless Célimène, she enters the room. Alceste begins a lengthy tirade about Célimène's perfidy, the blows he has been dealt by fortune, and the inability of his reason to restrain his passions. He presents the letter to Célimène with a melodramatic flair and she seems to glance at it, amused, saying "you are indeed a strangely foolish man!" The lovers' quarrel jumps back and forth as Alceste accuses Célimène of perfidy, and she accuses him of not loving her. At one moment Alceste is angry and at another he is apologetic. Finally the coquette wins out; she pouts and says "no, you don't love me as you should." Alceste exclaims "Ah! my love is beyond all comparison."
The conversation is interrupted by the entrance of Alceste's stumbling manservant, DuBois. The servant hems and haws and then finally tells the exasperated Alceste that a strange man "with a face as black as his coat" came and left some papers about the lawsuit process. An hour later another man came and warned DuBois that his master was in danger. He left a written message to be delivered to Alceste. Alceste, disturbed by the fact that he has been interrupted in his conversation with Célimène, goes off to see what it all means.
There is both comic reversal and comic discrepancy illustrated in this scene. At first, we see Alceste raging with anger and in contrast, a serene, coy, and clever Célimène. Alceste's actions are typical here: He is repeatedly exasperated with Célimène and can never really function as the perfectly rational man. Gradually during the scene, there is a comic reversal as Célimène's ire grows in tempo until Alceste is forced to try and placate her. The exchange of roles by the characters within this one scene adds to the comedy of the situation. Furthermore, this entire scene seems to substantiate Célimène's characterization of Alceste in Act II. That is, he seems to be contrary for its own sake; first he berates Célimène, then when she counters and berates him he takes the opposite role and swears innocence.
Alceste finally recognizes what she is doing; he is the would-be rational man who has lost control and has to admit it: "Perfidious creature, how well you know how to turn my weakness against me and exploit it to your own purposes the fatal and excessive love those faithless eyes inspire!" Ironically, he progresses from being accusing and spiteful toward her to being the supplicant who is apologetic. The basis of the scene is that he wants her to prove to him that she has not been unfaithful, yet she never cares to.
Before Alceste can bring Célimène to some type of terms, he is interrupted by his servant, who brings news that he has lost his long-pending lawsuit. The servant here is a stock figure who cannot manage to deliver the message until his master is totally exasperated. The reader should remember that Alceste is already exasperated by Célimène, who would not give him any direct answers; the appearance of the servant who can't deliver a straight message is a further means of exasperating Alceste and of evoking laughter. Alceste takes out his anger against Célimène by being harsh with his servant.
Molière ends the act by having Alceste's philosophical honesty interfere with his life because once again he must interrupt his life to tend to a lawsuit against him. His unswerving honesty does not allow him to live without the constant harassment by the society which he ultimately rejects.