Alceste
Alceste is neither a purely comic character nor a tragic one. In some ways he evokes the sympathy of the audience and/or the reader, especially when he is contrasted with the hypocritical, artificial characters of the court gossips (for example, Acaste and Clitandre), or with the flighty coquetry of Célimène. Yet Alceste's obsession with plain speech leads to a number of humorous consequences in the play.
Philinte
The portrayal of Philinte, who accepts everyone as they are, runs the risk of blandness. Yet his uses of ingenious argument to counter Alceste's extremism command the respect of the audience. Philinte supplies a much-needed calming counterweight to the explosive passion of Alceste. Molière hints that Philinte's self-imposed task is difficult, if not impossible, by showing him run full circle: just as he is attempting to calm Alceste at the beginning of the first scene, he has the same goal at the end of the final scene.
Oronte
Oronte is foppish, egocentric, and insincere. He competes with Alceste for the favor of Célimène. He also causes Alceste trouble, as in the affair of the Marshals and the charge that Alceste has authored a dangerous work. As Célimène warns Alceste, the fops and gossips at court may not contribute anything positive to society, but they can cause significant harm and injury to others who do not curry their favor.
Célimène
Célimène is humorous, clever, and coquettish. She is especially skilled at identifying and mocking the foibles of noble courtiers This attribute of Célimène is particularly evident in Act 2, Scene 5 (the "portrait scene") in which Célimène gives delightfully satirical capsule sketches of some strikingly eccentric or self-important courtiers. Eventually, however, she overplays her hand and is left alone.
Arsinoé
Arsinoé is a preeminent example of hypocrisy in the play. She criticizes her fellow courtiers for their loose morals, but she fails to practice what she preaches. Indeed, her elaborately planned backstabbing makes her detestable. Ultimately, she fails to establish any rapport with Alceste, despite her best efforts to court his favor and undermine his relationship with Célimène.