In reply to John V. Canfield's recent article, 'Wittgenstein and Zen', 1 I have one main point to make: it is important to understand that thoughts are empty, and not that minds can be empty of thoughts. Canfield's central idea is that for both Wittgenstein and Zen, language and understanding do not require thought. The Zen ideal is to live free of thoughts, but in such a way that one can still do ordinary things, including speaking meaningfully and, most important, understanding what is said by others. This, we are told, is clarified by Wittgenstein's insistence that understanding a sentence does not involve the positing of a series of mental acts or processes; or in other words does not require thoughts. I think that Canfield has gone wrong in his interpretation of Mahdydna Buddhist philosophy, but there is nothing the matter with his understanding of Wittgenstein. He sets out the way in which Wittgenstein rejects a certain picture of understanding (or, for that matter, knowing, willing, meaning and others)-a picture of these as internal processes with which I can be privately acquainted. If we understand a sentence, we do not do it by comparing the words in it with our private images of their meanings. We 'just understand' the original sentence. Language is ultimately grounded, not on thoughts, but on 'just doing' things, as Canfield says. His more contentious claim is that it is possible to manage without thoughts altogether, by 'just doing' things. The crucial link with Zen is that Nirvana or enlightenment is simply 'acting without thought'. According to Canfield, the enlightened person is able to do everything we can do, but he 'just does' it. All that stands between us and enlightenment is our thoughts, which cover up the fact that understanding is operating quite well without them. The enlightened and the unenlightened person are both able to use and understand words properly, and what unites these two is certain underlying 'practices'-the fact, for instance, that both of them, when asked to bring a red flower, bring a red and not a blue one. Their agreement in the use of words is not based on the supposition that the word 'red' refers to something; perhaps to an essence of red with which each can be privately acquainted and take a peep at when he needs to understand a sentence containing the word 'red'.