Because of Plato's attacks on the sophists, Isocrates' school — having its roots, if not the entirety of its mission, in rhetoric, the domain of the sophists — came to be viewed as unethical and deceitful. Yet many of Plato's criticisms are hard to substantiate in the actual work of Isocrates; at the end of "Phaedrus", Plato even shows Socrates praising Isocrates (though some scholars have taken this to be sarcasm). Isocrates saw the ideal orator as someone who must possess not only rhetorical gifts, but also a wide knowledge of philosophy, science, and the arts. He promoted the Greek ideals of freedom, self-control, and virtue; in this he influenced several Roman rhetoricians, such as Cicero and Quintilian, and influenced the core concepts of liberal arts education.