The first occasion of his eager inclination to oratory, they say, was this. Callistratus, the orator, was to plead in open court for Oropus, and the expectation of the issue of that cause was very great, as well for the ability of the orator, who was then at the height of his reputation, as also for the fame of the action itself. Therefore, Demosthenes, having heard the tutors and schoolmasters agreeing among themselves to be present at this trial, with much importunity persuades his tutor to take him along with him to the hearing; who, having some acquaintance with the doorkeepers, procured a place where the boy might sit unseen, and hear what was said. Callistratus having got the day, and being much admired, the boy began to look upon his glory with emulation, observing how he was courted on all hands, and attended on his way by the multitude; but his wonder was more than all excited by the power of his eloquence, which seemed able to subdue and win over any thing. From this time, therefore, bidding farewell to other sorts of learning and study, he now began to exercise himself, and to take pains in declaiming, as one that meant to be himself also an orator. He made use of Isaeus as his guide to the art of speaking, though Isocrates at that time was giving lessons; whether, as some say, because he was an orphan, and was not able to pay Isocrates his appointed fee of ten minae, or because he preferred Isaeus's speaking, as being more business-like and effective in actual use.