Conjecture and explanation: A reply to Reydon

Reydon (2012) comments on my account of how-possibly explanation (Forber, 2010). I distinguish between three types of explanation (global how-possibly, local how-possibly, and how actually) and argue that these distinctions track various roles explanations play in evolutionary biology. While Reydon accepts the distinctions, he questions whether the two different types of how-possibly explanation count as genuine explanations. He summarizes his analysis with a slogan: “global how-possibly explanations are explanations but not how-possibly; local explanations are how-possibly but not explanations.” Reydon’s commentary raises a number of insightful points, and I will not be able to address them all. Instead, after clarifying certain points in my original paper (4 1), I will respond to Reydon’s slogan by addressing whether global how-possibly explanations should count as explaining how possible (4 2), and what (so-called) local how-possibly explanations are, if not explanations (4 3).     

Animal signals: A reply to Hinde

Hinde has criticized articles by Dawkins & Krebs (1978) and Caryl (1979) in which supposedly traditional ethological views about agonistic display were contrasted with those arising from games theory. It is argued here that the views that we contrasted with those from games theory were not ‘straw men’: in particular, Cullen's view is completely incompatible with the predictions from games theory, and is well supported by ethological evidence (as conventionally interpreted). But an unusually detailed analysis of the ethological data, which raises many points for future studies, shows that the evidence actually favours the games theoretic view. Hinde argues that the conflict hypothesis of threat display implies that displays could not and should not carry precise information. The arguments he used in this context are not wholly satisfactory: in particular, explanations in terms of interaction are of little value unless details of the interaction can be specified. Clear hypotheses are needed in the analysis of animal communication, and ideas from games theory can be of help to ethology in this respect.     

A reply to Michael Coughlan

Ford's book on the question of when human personhood begins, When Did I Begin? Conception of the Human Individual in History, Philosophy and Science (Cambridge University Press; 1988), is reviewed by Michael J. Coughlan in this issue of Bioethics. Here Ford responds to Coughlan's review, focusing on three topics: the importance of rationality for personhood, how far back one can trace the ontological identity of what is indisputably a human individual and human person, and the difference between the awareness of the reality of human persons and the varying degrees of perception of their value in the family and society.     

Against the impairment argument: A reply to Hendricks

In an article of this journal, Perry Hendricks makes a novel argument for the immorality of abortion. According to his impairment argument, abortion is immoral because: (a) it is wrong to impair a fetus to the nth degree, such as causing the fetus to have fetal alcohol syndrome (FAS); (b) it is wrong to impair a fetus to the n+1 degree (to cause the fetus to be more impaired than to have FAS); (c) killing the fetus impairs the fetus to the n+1 degree (causes it to be more impaired than to have FAS); (d) abortion kills the fetus; (e) therefore, abortion is immoral. The impairment argument is a promising account for the wrongness of abortion because it does not rely on the controversial metaphysical premise that a fetus is a person. This article aims to show, that despite some immediate advantages over the rival theories of the immorality of abortion there is a reason to believe that the impairment argument is untenable. That is because there are goods that can be achieved by abortion but that cannot be achieved by impairing the fetus.     

The explanatory power of biogeographical patterns: a reply to de Bruyn et al

Confusion between evidence and hypothesis in biogeographical studies was the focus of our recent Guest Editorial (Parenti & Ebach, 2013, Journal of Biogeography, 40 , 813–820). That editorial was critiqued by de Bruyn et al. (2013, Journal of Biogeography, doi: 10.1111/jbi.12166) to whom we reply briefly here. Despite our shared goals – to understand what lives where and why – we argue from different philosophical premises. Although we may have little common ground, such debate encourages the good health of the field of biogeography.