Gabriel Abend raises a number of interesting questions about philosophical methodology, in general and as it relates to our analysis. We are grateful that he does not think we are Platonists! We approach his questions by making two general points about the methodology we employ in the book.
The first point is that, although we focus on conceptual issues throughout our book, we do not offer (because we do not need to) a substantive theory of “concepts” or a specific theory of “conceptual analysis” as such. Therefore, in the book we don’t attempt to offer answers to some of the more vexing issues that arise for theories of the latter (such as the roles of intuitions, ordinary meanings, or the concept-conception distinction). As we note in the book, the approach we take is more method (and a largely pragmatic one) than doctrine and also corrective/ therapeutic in nature. We take the claims and arguments as we find them, and—rather than imposing a top-down theory—we attempt to root out mistaken inferences and conclusions that arise because of conceptual confusion somewhere in the claims or arguments. The concepts at issue may involve ordinary language, specialized terms in legal doctrine, scientific concepts, or stipulated concepts. (We will demonstrate below with a couple of examples of how our arguments work.)
The second point is that nothing in our arguments depends on being able to specify necessary and sufficient conditions for concepts. In addition, we acknowledge that concepts may be vague; that they can change; and that in some cases there may be substantial disagreement about the content of a concept (for example, is it a “lie” if someone says something believed to be false, but they were mistaken and what they said is actually true—or rather did they merely “attempt to lie” and fail?). This point also answers some of the concerns raised by Moriarty and Shen (and Francis’s comment to Jane’s post). An emphasis on conceptual clarity does practical work on the ground even if there is no agreed-upon theory of the scope, contours, and relationships for the relevant concepts (for example, necessary and sufficient conditions for pain).
With these two points in mind, we think the best way to respond to Abend’s abstract questions is with a couple of concrete examples.
1. The voluntary act requirement in criminal law (“actus reus”). Criminal liability typically requires proof of a willed act by the defendant. The criteria for this requirement are provided by legal doctrine. Now, consider the claim that neuroscience informs this category by revealing whether a movement is willed or not. However, suppose the argument for this relies on the following two assumptions: first, that the voluntary act element requires an “internal process of deciding to act” and “a feeling of deciding to act” and, second, that neuroscience can illuminate whether this internal process or feeling was present. One way to respond to this argument, as we do, is to point out examples of conceptual confusions with the underlying assumptions. For example, the voluntary act requirement does not, as is being assumed, require an internal decision to act or the feeling of such a decision. Therefore, the argument does not go through. This is our principal point: the assumptions in play are not plausible.
2. Knowledge. As Abend points out, there are many different theories of knowledge (and epistemologists are continually refining existing ones and creating new ones). Conceptual clarity matters for the neurolaw context, however, even when there is vigorous ongoing debate about the nature of knowledge. For example, propositional knowledge is—whatever else it may be—“factive.” To know something implies that what is known is true. One aspect of knowledge, in other words, involves an appropriate connection to the world. The failure to recognize this point leads to conceptual confusion in a variety of claims and arguments about whether knowledge of various sorts is “in the brain.” Given this factive component, knowledge is not “in the brain” because the very same brain state may exist regardless of whether the person has knowledge. (This does not mean that a brain is not necessary for knowledge.)
Here is a concrete example (a modified version of this famous one). Suppose someone is driving along a highway and sees a barn (a real barn) and asserts, “there’s a barn.” Hours later, the same person sees what he perceives to be a similar looking barn and again asserts, “there’s a barn.” Unbeknownst to the driver, however, the second time he is in Fake Barn County, where they make barn facades along the highway to trick passing motorists. Our driver, let’s assume, has similar perceptual experiences both times and forms similar underlying brain states. Yet, in the first scenario he has knowledge, and in the second he does not. Thus, knowledge is not his brain states, which, by hypothesis, were the same. Again, to be clear, this is not to deny that in some cases there may be neurological differences between cases of knowing and non-knowing.
Exactly how our specific arguments relate to the abstract issues raised by Abend raises several interesting questions about philosophical methodology. Our discussions regarding the usage of concepts in the neurolaw context, we assume, have some bearing on theses issues. But it would require an entirely new book to answer these meta-theoretical issues. Again, interesting as they are, we do not think they are questions we need to answer, at least so far as the arguments in our book are concerned.