The act begins on a Venetian street with the subplot figures of Sir Politic Would-be and Peregrine. Sir Politic is informing and instructing Peregrine on politic behavior. First, Peregrine must never speak the truth. Furthermore, he must profess no religion, learn to handle silver forks at meals, and know the time to eat melons and figs. Peregrine wonders that these diverse points are all equally matters of state.
Sir Politic boasts that he has been among the Venetians for fourteen months and within the first week of his landing they all thought him native born. He searches daily for one he can trust. If he finds such a creature, he will make him rich. Sir Politic's fertile mind has conceived of some ingenious projects. One of his most impressive ideas concerns the quarantine of ships from the Levant that are suspected of having plague aboard. Instead of lying forty or fifty days at the pesthouse, Sir Politic will save that charge and loss to the merchant.
First, I bring in your ship 'twixt two brick walls — but these the state shall venture. On the one I strain me a fair tarpaulin, and in that I stick my onions, cut in halves; the other is full of loopholes, out of which I thrust the noses of my bellows. . . . Now, sir, your onion, which doth naturally attract th' infection . . . will show instantly, by his changed color, if there be contagion.
Sir Politic shows Peregrine his personal dairy, wherein it is written when last the Englishman used the privy. These are politic notes, insofar as Sir Politic wrote them.
After the headlong pace of Act III's conclusion, Jonson wisely begins Act IV with the subplot. The playwright has reached a comic peak, and he must begin building the plot to its final resolution. Jonson could not hope to keep the audience laughing as it should be at the end of the last act. The audience needs a chance to catch its breath and digest the meaning of the preceding action.
Once again, the first scenes of an act take place in the street, and their unity of action is the subplot of Sir Politic. Sir Pol is mocked in this sequence as the typical English tourist. It would still be a good joke in the England of today. The English never seem to change their native habits when they travel abroad. "Only mad dogs and Englishmen," wrote Noel Coward, "go out in the midday sun."
The fantasy of Sir Politic's thought is exposed in several ways. To begin with, he cannot keep his advice from contradicting his aspirations. He warns Peregrine against telling the truth, and in the next breath he tells his fellow tourist that he is looking for someone he can trust! Next, his idea of scientific method is exposed in the onion plan. Finally, we are shown that he hasn't the slightest notion of what is important or not important by the notes he takes of his daily business. Forks and religion, melon and figs, onions and privy — all are of political moment.
In this scene, Jonson indulges himself in the English penchant for self-mockery. Oscar Wilde, George Bernard Shaw, Noel Coward, and John Osborne have continued that tradition into our time.