Why Evolutionary Biology is (so Far) Irrelevant to Law

BRIAN LEITER
University of Texas at Austin - School of Law & Department of Philosophy
MICHAEL WEISBERG
University of Pennsylvania October 17, 2007

Abstract:
Evolutionary biology - or, more precisely, two (purported) applications of Darwin's theory of evolution by natural selection, namely, evolutionary psychology and what has been called human behavioral biology - is on the cusp of becoming the new rage among legal scholars looking for interdisciplinary insights into the law. We argue that as the actual science stands today, evolutionary biology offers nothing to help with questions about legal regulation of behavior. Only systematic misrepresentations or lack of understanding of the relevant biology, together with far-reaching analytical and philosophical confusions, have led anyone to think otherwise.

Evolutionary accounts are etiological accounts of how a trait evolved. We argue that an account of causal etiology could be relevant to law if (1) the account of causal etiology is scientifically well-confirmed, and (2) there is an explanation of how the well-confirmed etiology bears on questions of development (what we call the Environmental Gap Objection). We then show that the accounts of causal etiology that might be relevant are not remotely well-confirmed by scientific standards. We argue, in particular, that (a) evolutionary psychology is not entitled to assume selectionist accounts of human behaviors, (b) the assumptions necessary for the selectionist accounts to be true are not warranted by standard criteria for theory choice, and (c) only confusions about levels of explanation of human behavior create the appearance that understanding the biology of behavior is important. We also note that no response to the Environmental Gap Objection has been proffered. In the concluding section of the article, we turn directly to the work of Professor Owen Jones, a leading proponent of the relevance of evolutionary biology to law, and show that he does not come to terms with any of the fundamental problems identified in this article.

Might Intelligent Design turn out to be right?

I am going to argue that for all anybody knows, evolutionary science might develop in such a way that an Intelligent Design (ID) argument would be plausible. Hence, while one might well be justified in saying that ID arguments right now do not work, one is not justified in saying that future ID arguments won't work given a fully developed evolutionary science. Moreover, our current state of biological knowledge, interpreted in an uncontroversial and friendly way, gives us relatively little, if any, reason to accept the claim that ID arguments won't work given a fully developed evolutionary science. (In the interests of full disclosure I should say that I do not think any extant ID argument succeeds in establishing the existence of a designer.)

I shall understand a successful ID argument for a design hypothesis H (say, that God has designed the world) to be an argument that starts with some biological fact F about the world going over and beyond the mere existence of life, a fact such as that the world contains intelligent life, or that the world contains the mammalian eye, or that the world contains highly complex organisms, and then argues:

1. F is very unlikely to happen if the only processes in play are those of evolutionary biology.
2. F is not unlikely to happen on the relevant design hypothesis H.
3. Therefore, F provides significant evidence for the design hypothesis over and against the hypothesis that the only processes in play are those of evolutionary biology.

Assuming that before we give the argument our probability for our design hypothesis (say, that God exists and has created the world) is not too low, we're going to get a successful ID argument as soon as we can find a biological fact F satisfying (1) and (2). My claim, now, is that the present state of evolutionary science gives us little reason to believe that we will not find such a fact F. Note that the above is not the only way of formulating an ID argument. But if we are not in a position to know that no ID argument of this sort is successful, then we are likewise not in a position to know that no ID argument of some sort or otheris successful….

Bugs Bunny!