Over the past few years considerable attention has been paid to a variety of issues that are now placed collectively under the heading of “Neuroethics”. In both the academic and the popular press there have been discussions about the possibilities and problems offered by cognitive enhancement (memory enhancement, “smart” pills, brain implants) and neuroimaging (lie detection, “mindreading”) as well as debate about the implications of these emerging “neurotechnologies” for morality and the law. This issue of the journal contains eight papers that discuss a broad range of important topics in neuroethics, from cognitive enhancement and the moral status of animals and cyborgs, to the challenges of neurological consults in end of life cases. As these papers demonstrate, advances in neuroscience raise a number of important ethical questions, but can neuroscience help provide any answers?

FACT AND VALUE

According to the received philosophical wisdom, there is a fundamental distinction between fact and value—between how things are and how they ought to be. On the basis of this distinction one cannot draw normative conclusions from descriptive premises because there is nothing in the premises that would warrant such conclusions: from the fact that happiness is desired it does not follow that it ought to be. This received wisdom applies to neuroethics in the following way: whereas neuroscience might be able to identify the neurophysical correlates for evaluative notions such as preferences and attitudes,^1,2 lying,³ and the distinction between in control and out of control behaviour,⁴ neuroscience cannot, in and by itself, provide the basis for their evaluation. The reason for this is that, in the absence of factors external to these neurophysical states, one neurophysical state is no better or worse than another—internal neurophysical states are logically …