AbstractNeuroscience is commonly thought to challenge the basic way we think of ourselves in ordinary thought, morality, and the law. This paper: (1) describes the legal institutions challenged in this way by neuroscience, including in that description both the political philosophy such institutions enshrine and the common sense psychology they presuppose; (2) describes the three kinds of data produced by contemporary neuroscience that is thought to challenge these commonsense views of ourselves in morals and law; and (3) distinguishes four major and several minor kinds of challenges that that data can reasonably be interpreted to present. The major challenges are: first, the challenge of reductionism, that we are merely machines; second, the challenge of determinism, that we are caused to choose and act as we do by brain states that we do not control; third, the challenge of epiphenomenalism, that our choices do not cause our actions because our brains are the real cause of those actions; and fourth, the challenge of fallibilism, that we do not have direct access to those of our mental states that do cause our actions, nor are we infallible in such knowledge as we do have of them.