They go off to the house of Kallias, where Protagoras and other Sophists are staying. The porter is so worn out by the number of visitors that he is distinctly rude. They find Protagoras walking up and down in the cloisters of the house, with three or four listeners on either side, one of whom is learning to be a Sophist himself. Behind follows a crowd, mostly composed of the foreigners whom he draws from city to city, like Orpheus, with his magic voice. Another Sophist, Hippias, is sitting on a sort of throne in the opposite part of the cloisters; around him on benches are a number of inquirers, who were asking him questions about natural science and astronomy. A third Sophist, Prodikos, is in a side-building, still in bed, covered up in blankets.[511] His audience sat on neighbouring beds. The whole assemblage finally collect couches and benches together in a great circle to hear a discussion between Sokrates and Protagoras. Kallias, the host on this occasion, often entertained Sophists: at another time he had Gorgias and Polos in the house. His cloisters must have provided a favourite lecture-room. The Sophists also haunted the gymnasia. The discussion in the _Euthudemos_ takes place in the undressing-room of the Lukeion: the two Sophists have been walking in the cloister. Hippias on one occasion lectures in a school-room, on another in a public place at Olympia. Protagoras was the first of these teachers to take pay. His system was very fair. On the close of their course of instruction his pupils, if they chose, paid the fee for which he asked; otherwise, they went into a temple, and, after taking an oath, paid as much as they said his instruction was worth.[512] Hippias made about £600 in a very short time in Sicily, receiving some £80 from the tiny town of Inukos, although Protagoras was also lecturing in the island at the time. Prodikos charged £2 for a particular lecture on correct speech,[513] but there was also a less complete form of it which cost only 10d.; he seems to have been noted for the gradations in his charges, for there were also lectures at 5d., 1s. 8d., and 3s. 4d.[514] The sum which Euenos of Paros asked for teaching the whole duties of a man and a citizen was £20.[515] Probably, however, the charges of these Sophists, and the money which they made, were much exaggerated by their contemporaries. Isokrates, the pupil of Gorgias, gives a much lower estimate. “None of the so-called Sophists,” he says, “will be found to have collected much money. On the contrary, some passed their lives in poverty and the rest in quite ordinary circumstances. The richest Sophist within my memory was Gorgias. He spent most of his time in Thessaly, the most prosperous part of Hellas. He lived to a great age and followed his profession for a great many years. He did not take upon himself any public burdens by settling in any one city. He did not marry or have children to bring up. Yet with all these