I expect you to be sincere and as an honourable man never to utter a single word that you don't really mean.
Uttered by Alceste in the opening scene of The Misanthrope, this line quickly establishes Alceste's extreme value system. His expectation that Philinte never say a single dishonest word is somewhat of a ridiculous request; we immediately recognize that Alceste will be impossible to please. Alceste's comment seems especially extreme juxtaposed with Philinte's rational defense of the practice of occasionally bending the truth. With this quotation, then, Molière establishes the central conflict of the play—Alceste's unwillingness to forgive the faults of his fellow man. Molière also defines Alceste's supposition that he somehow carries higher status than his acquaintances. Alceste expects Philinte to behave a certain way—implying that Philinte has an obligation to do so.
Additionally, this line helps set the comic tone of the play. Departing from his earlier comedies, Molière focuses his satire on human behavior rather than attacking larger classes and social system. Alceste is not the typical farcical stereotype, but he does represent extreme values. In this sense, he is the caricature of a prudish grump. Over the course of the play, Molière dissolves this particular image of Alceste, but it never disappears completely.
There's a season for love and another for prudishness, and we may consciously choose the latter when the hey-day of our youth has passed—it may serve to conceal some of life's disappointments.
This passage from Act III, scene iv, captures Célimène's carefree—and often careless—spirit, as she speaks to Arsinoé. Célimène realizes that her youth is limited, so she therefore makes no apology for the freedom from propriety that youth affords her. Her words reveal a certain understanding of the cycle of life. She shows keen insight in blaming Arsinoé's age, rather than a character flaw, for the older woman's behavior.
Célimène's words also touch upon a deeper theme in the play—that of masking one's true self. She mentions that age might be used to "conceal," to distance oneself from the pains and prejudices of life. Age is only one of a variety of concealments applied in The Misanthrope. Even Célimène appears to be hiding her true feelings from Alceste. We cannot discern whether or not she really loves him, but it is likely that she cares for him more than her words might suggest. In this way, Célimène's mask is her language.
I'll confront her in no uncertain terms with her villainy, confound her utterly, and then bring to you a heart entirely freed from her perfidious charms.
In speaking to Éliante about Célimène's "villainy," Alceste suggests his belief that he can reason his way out of love. He thinks that by voicing his rightness to Célimène he might somehow be "entirely freed." Alceste also seeks revenge. In this light, we might find disturbing his idea that revenge might repair the situation.
Of course, Alceste's diatribe denouncing Célimène's deception might also represent his method of quieting his own inner voice that tells him the truth of his love for her—that no matter how anguishing his attraction, he will not be able to extinguish it. Alceste's words to Élainte are, in part, a form of denial: Alceste hopes that by making his anger public he might somehow be held to his own moral standard, enabling him to escape the consequences of his emotions. Despite his efforts, Alceste is unable to free himself from Célimène after he chides her for her wrongdoing. He holds true to the first part of his claim, that he will—"confront her in no uncertain terms"—but he is unable to adhere to his vow to attain his heart's freedom.
The failings of human nature in this life give us opportunities for exercising our philosophy, which is the best use we can put our virtues to. If all men were righteous, all hearts true and frank and loyal, what purpose would most of our virtues serve?
Here, Philinte exposes the basic weakness of Alceste's approach to life, demonstrating that humankind would likely lose its vitality if Alceste's theories were applied to the whole of society. Philinte argues that flaw and failure give rise to character and invention. Veritably, if Célimène and the other victims of Alceste's scorn did not behave as they do, Alceste would have nothing to gripe about, which would rob him of a significant part of his personality. Philinte points out this irony to Alceste. The merit of Alceste's code of honor and ethics derives largely from the foul behavior of those whom he observes. Were they to share his values, society would be homogeneous, even boring. Philinte's comment also suggests that human differences make life worthwhile. Alceste's misanthropy might be directed against the very flaws that make human interaction interesting.
You shall observe me push my weakness to its furthest limit and show how wrong it is to call any of us wise and demonstrate that there's some touch of human frailty in every one of us.
Though Alceste still intends to forswear the company of others, by the time this quotation appears (in Act V, scene iv) he begins to show signs of change. His earlier pretentiousness appears to have diminished as he admits, indirectly, to his own "frailty." At last, Alceste caves to his own emotion. However, he does not fully come to terms with his weakness. He reluctantly confesses his own shortcomings; he does not embrace them. Alceste has not yet learned that one can be both "wise" and at fault. He is a man of extremes. By his logic, if he is not "wise" then he must be "frail."
With the play's ending—which comes shortly after this quotation—Molière demonstrates just how tenuous Alceste's transformation is. When Célimène rejects Alceste's proposal that she leave society behind and come with him, he immediately regresses. Nonetheless, the hint of change remains, leaving us with the hope that Alceste might one day be both accepted and accepting.