I first became aware of Seagrave's work from reading his series of articles on the political theory of natural right, natural law, and natural rights.
While I agree with him on many points, I disagree with him on some fundamental points. The primary source of our disagreements is that Seagrave accepts Leo Strauss's claim that modern natural science--and particularly Darwinian science--subverts any idea of nature that would support natural right, natural law, or natural rights, while I argue against Strauss in defending the idea of Darwinian natural right.
Our disagreement is evident in Seagrave's recent article--"Darwin and the Declaration"--in Politics and the Life Sciences (vol. 30, no. 1, spring 2011, pp. 2-16). He disputes my argument that Darwinian evolutionary science can support the reasoning for natural rights found in the Declaration of Independence and in the argumentation of John Locke that stands behind the Declaration.
Seagrave asserts--and I agree--that the philosophical teaching of the Declaration of Independence assumes both the distinctness and the dignity of the human species. Human beings must be naturally distinct in being different in kind from all other species of animals. And this natural distinctiveness must give human beings a natural dignity as being morally superior to all other species.
According to Seagrave, I fail to recognize how Darwin's evolutionary science contradicts both of these points. Contrary to the first point, Darwin claims that human beings as products of evolution are different in degree but not in kind from other animal species, and thus Darwin denies the essentialist conception of species implicit in the Declaration of Independence and in Locke's reasoning. Contrary to the second point, Darwin grounds the moral dignity of human beings in the evolution of a "moral sense" that depends upon the moral sense tradition of philosophy--from Francis Hutcheson to David Hume and Adam Smith--which assumes a natural sociality that denies the Locke's reliance on natural selfishness and individualism.
The specific points on which my arguments differ from Arnhart's account consist primarily in the following: 1) whether Darwinian evolutionary theory can support the conception of the human species or human nature that is sufficiently stable and distinct to cohere with the idea of natural or human rights found in the distilled Declaration; and, 2) whether "moral sense" philosophy can serve as an adequate or appropriate support for this idea of natural or human rights. While Arnhart clearly answers both questions in the affirmative, I have argued that significant and perhaps insurmountable obstacles to affirmative answers remain. (12)Most of what I would say in response to Seagrave can be found in previous posts here, here, here, here, here, here, and here.
I'll add just a few points here. First, Seagrave fails to consider the possibility that the reality of human nature as required for the Lockean argument and the Declaration of Independence can be grounded in a biological concept of species that is opposed to Platonic essentialism. That Locke draws from the Aristotelian biological tradition of understanding species is evident when one notices the passages in the Essay Concerning Human Understanding that are almost direct quotations from Aristotle's biological writings. For example, Locke's comments on how "we shall find everywhere that the several species are linked together, and differ but in almost insensible degrees" (3.6.12; 4.16.2) echo passages in Aristotle's Parts of Animals (681a10-15). Like Locke, Aristotle is criticizing the Platonic tradition of essentialism and defending a biological concept of species rooted in an empirical science of natural history. This biological tradition of thought from Aristotle to Locke is renewed in Darwin's evolutionary account of species, in which emergent differences in kind arise from differences in degree that pass over a critical threshold of complexity. So, for example, we can explain the distinctiveness of the human mind as an emergent product of the evolution of the primate brain as it increased in size and complexity.
If one assumes, as Seagrave seems to do, that Platonic essentialism is the only way to explain the reality of species, then Locke and Darwin will appear to be nominalists who deny the reality of species. But if one sees the reasonableness of the biological concept of species, then one can see how Locke and Darwin can affirm species as stable realities that we can know by an empirical natural history of probabilistic science.
My second point is to deny Seagrave's sharp contrast between Lockean individualism and individual rights, on the one hand, and the Scottish moral sense philosophy, on the other hand. I am not convinced that Lockean individual rights require a political morality that denies human sociality and the concern for the public good, which would set Lockean individualism in opposition to the moral sense school.
Actually, Seagrave recognizes that Thomas Jefferson--the primary author of the Declaration of Independence--thought that Locke's arguments and the moral sense philosophy were compatible. Seagrave explains this by asserting "that Jefferson himself simply overlooked, or failed to fully grapple with, the significant yet rather subtle tensions between a Hutchesonian public good-based political philosophy and a Lockean rights-based one" (11). Does Seagrave really want to assert that he understands Jefferson's Declaration better than Jefferson himself did?
Jefferson's Declaration begins by invoking the rights of individual "men." But then it moves to the rights of "the People." Seagrave says nothing about this, because in concentrating on the opening sentences of the Declaration, he ignores the rest of the Declaration that speaks of "the People" rather than individual "men." Most importantly, the right of revolution--the right exercised in the Declaration of Independence itself--is said to be a right of "the People." This thought is carried into the U.S. Constitution, which appeals to the authority of "We the People," with no references to the rights of "men."
This move from the individual rights of "men" to the social rights of "the People" is evident in Locke's Two Treatises, which reflects the complexity of human nature as both selfish and social. Seagrave says nothing about this.
Throughout the Two Treatises, Locke indicates that the rights of individuals are constrained by society and the public good. For example, private property is constrained by the rule that there must be "enough, and as good left in common for others" (ST, 27). Human beings are driven into society by their dependence on parental care as children, and the family is the "first society" (ST, 77). Like Aristotle and Darwin, Locke explains the natural sociality of human beings as arising from their biological nature as mammals with extended periods of childhood dependence on parental care. Not only do human beings have a natural desire to care for themselves and their survival, they also have a natural desire to care for their children and other family members as extensions of themselves (FT, 86-97; ST, 52-86). Once individuals leave the state of nature to enter civil society, these individuals have authorized the society or the legislative power to act for the "public good of the Society" (ST, 89). In that society, individuals must submit to the rule of the majority. Moreover, the right of resistance to tyranny is not a right of every individual but a right of the people. Many individuals can suffer a deprivation of rights. But there will be no revolution until the majority of the people are moved to rebel (ST, 230). For as long as society lasts, the rights of individuals have been given up to the community (ST, 242).
This Lockean movement from the rights of individual men to the rights of the people is clear in the Declaration of Independence. Once government is said to be "instituted among men," the Declaration never mentions the "rights" of "men" again. Instead, the Declaration speaks of the "rights" of the "People."
My point here is that Locke and the Declaration combine individual self-interest and social concern in a manner that is close to what one sees in the moral sense philosophers and Darwin. Human beings naturally care for themselves, but they also naturally care for others whom they identify as extensions of themselves. Darwin explains this as a manifestation of evolved human nature. Modern social neuroscience deepens this explanation by showing how human neuroendocrine systems are adapted to sustain our self-conscious care for our embodied identity and for others as mammalian extensions of our ourselves.