1. Jealousy
Leontes' jealousy is treated more extensively by Shakespeare than in Greene's Pandosto. In fact, it takes over most of the first three acts, giving a highly charged, claustrophobic atmosphere. When this is replaced by the Arcadian act 4, the difference is so extreme that some critics find that it compromises the integrity of the play. Depending on how you read the play you might decide that Leontes jealousy happens suddenly, without warning at 1.2.108 ("Too hot, too hot"), or that it slowly brews up from the very beginning of the scene, with the first hint coming when Polixenes declares he has stayed for nine months (note that Hermione is innocent of infidelity, and nine months pregnant: if Leontes thinks that on arrival Polixenes got her pregnant, he must be "forgetting" what he himself did then). Throughout scene 1.2, Leontes is left out because he takes his own exclusion from the conversation too seriously, and is too serious about sex to joke about it, as Polixenes and Hermione do. Leontes' evil jealousy is rooted in a refusal to play, to let things (or, for that matter, his friend) go. His jealousy is necessary to the plot, but it is shown as rooted in human weakness, adding complexity and compassion to what is initially a fairy-tale scenario. In fact, the first three acts of the play are worthy of a tragedy like Othello in their psychological realism, Leontes presenting so much of the emotion he is concealing from the other characters to the audience that it creates considerable tension. In 4.4 Polixenes and Camillo are also concealing something from the other characters, but there is virtually no tension at all, simply a dramatic "surprise".
Jealousy is a major Shakespearian theme, so it is not surprising that it is given so much weight here. How it is assessed has a huge influence over the play's reception, because it influences how we accept the ending of the play, whether we think Hermione does or should forgive Leontes. Furthermore, the fact that it is always men who are jealous affects the presentation of women and prompts us to ask why it should be that in this play women are the objects of men's folly and redemption.
2. Remarriage, reconciliation, renewal
The happy ending of the play occurs in two parts. The recovery of Perdita, which was the whole of the happy ending of Greene's Pandosto, and the restoration of Hermione, Shakespeare's own invention. Shakespeare does not even stage Perdita's recovery, giving 5.3 great significance. Unlike the ending of a romantic comedy - marriage, effectively - this ending is a re-marriage, a re-assertion. Similarly, someone who is already alive "comes to life" completely convincingly. It is hard to imagine a description of the events of 5.3 by the lords of 5.2 that wasn't a tautology: this is because Hermione's "resurrection" is only convincing as theatre. Its success is specific to the stage, implicating the audience because, like its parallel her trial, the very scene is about witnessing a person's truth. What the characters do on the stage reflects upon what the audience does to the stage.
The other part of the play that involves the stage to this extent is 4.4, a huge scene that contains much that is not dramatic but spectacular, even ritual. The sheep-shearing is a country festival of fertility and abudance, and Florizel and Perdita are figures of fertility, youth and renewal. The poetry which surrounds and creates Perdita is the lyric poetry of the present, simultaneously the here and now of a particular performance and an ideal, Arcadian present.
Reconciliation depends on forgiveness. Whilst 4.4 is a country scene which derives its energy from nature, the final scene of the play has overtones of art, religion and the supernatural, and it is from them that the possibility of reconciliation comes. There is a large scope for interpretation at the end of the play because while Hermione and Leontes are reunited, Hermione never says anything to Leontes. And sixteen unhappy years have passed, Mamillius and Antigonus are dead: renewal is not an accurate description of what has occurred. It is rather that the sheer improbability of events forces reconciliation.
3. Nature and Art
Polixenes and Perdita's disagreement in 4.4 about "nature's bastards" has often been extrapolated by critics who see the whole play as being about the relationship of art and nature. Nature does play an important part in the play, the cycle of seasons providing a structure for the entire cycle of loss and renewal, the countryside and pastoral tradition standing in massive contrast to the Leontes' sick court. Art on the other hand does not play such a large part, the only example of high art being the statue by "nature's ape", Julio Romano, which is not a statue at all. The opposition of nature and art should be divided into two others. The first is that of the court and the country, the sophisticated and the simple, which reflects upon the idea of nobility (conceived of as "natural"), especially when the Shepherd and Clown are made into gentlemen. The second is between honesty and disguise, especially apparent in Perdita who dislikes "playing a part" because she sees it as a kind of lying. In this she is rather like her father, who also has problems with playing, and with having a part, the very nexus of an individual's relation to the group.
Leontes and Autolycus are similar in that their participation in a group is destructive or deceitful. Leontes thinks he can perceive the truth better than anyone else, and his superior sense only creates unhappiness. Autolycus has more "sense" than the sheepshearers, and that is why he can rob them while they are all held "senseless" (but together) by his music. The difference is that Autolycus' villainy is picaresque where Leontes' is destructive, and Autolycus uses artifice where Leontes only has delusion. Perdita is a figure who is naturally artful, she has a grace that exemplifies what art and nobility should be, without any self- consciousness, which makes her natural. She can also be seen as an achievement of Shakespeare's poetry, in which case the ethical aspect of the nature / art opposition concerns Shakespeare himself and his art, which the audience can condone or condemn as "false". This approach is supported by the way the word "piece" is used in the romances to refer to women. Perdita is a "fresh piece of excellent witchcraft" (4.4.423), "the most peerless piece of earth... That e'er the sun shone on" (5.1.94-5), while the statue of Hermione is "a piece many years in doing and now newly performed by that rare Italian master, Julio Romano" (5.2.94-6). The effect is to make the heroine of the romance a synecdoche of theatrical performance itself, something seductive, both true and not true, something and nothing.