 Aristotle continues in a way that is highly relevant to discussions of skeptical language and action. A person who wishes to deny that things cannot be and not be at the same time has two options. Either they say nothing, or they talk to us. In the first case, there is no need for us to refute them. This person is like a plant—they do not talk. In the second case, either their utterance signifies something, or it signifies nothing. If it signifies something, then they say that something is so-and-so (which Aristotle takes to be self-defeating for them). If it signifies nothing, then it does not qualify as speech. Even though they make an utterance, the person is in effect not speaking with us (or to themselves). Aristotle also explains the plant-metaphor in terms of action (1008b10-30). A person who believes nothing is like a plant because they cannot act. Pursuit and avoidance testify to the fact that people have beliefs. (On Aristotle and skepticism, see the papers collected in Irwin 1995.)