Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 689-712:
Peterson argues that there are three broad ranges of interpretation of emergence: reductive, nonreductive, and radical. His goal in this essay is twofold: first, to categorize the primary senses of emergence as they occur in relevant fields of philosophy, theology, and science; second, to suggest how these different senses may be useful for the theology-science dialogue.[1]
“Systems at each hierarchal level have two properties. They act as wholes (as though they were a homogeneous entity), and their characteristics cannot be deduced (even in theory) from the most complete knowledge of the components, taken separately or in other combinations. In other words, when such a system is assembled from its components, new characteristics of the whole emerge that could not have been predicted from a knowledge of the constituents.”[2]
“Emergences thus occur both in model systems and in real world situations. If the models are well chosen, the two kinds of emergences map onto each other. They resonate with each other. In both cases, emergence leads to novelties: the whole is somehow different from the sum of the parts.”[3]
Peterson suggests that seven elements of the emergentist position need to be explored and enunciated carefully in order for emergentist positions to be coherent. One requirement of an emergent entity is that it be capable of some kind of higher-order description. Second, it is typically claimed that these emergent wholes obey various sorts of higher-order laws. Claims of higher-order description and higher-order laws lead to a third claim for emergent entities, that of unpredictable novelty. Fourth, emergence positions imply that lower-level parts are necessary for the existence of the whole. Fifth, lower-level entities are insufficient for emergent entities. Sixth, some emergent entities are capable of top-down causation, that is, they are causally efficacious. And finally, emergent entities are characterized by multiple realizability.[4]
Peacocke speaks of top-down causation as a “flow of information.”[5] Peterson notes that “[n]onreductive physicalists, as well as other emergentists, sometimes identify emergent entities with information.”[6] It must be noted that Clayton is, according to Peterson’s classification, a radical emergentist.[7] Radical emergentists emphasize both epistemological and ontological openness. Another example of the use of radical emergence within the context of the science-theology dialogue is the work of John Haught, even though he does not use the emergent terminology as per se.[8] Radical emergence is good for both theology and science; nevertheless, radical emergence also has its dangers, possibly leading to what might be referred to as an emergence of the gaps.[9]
For Dawkins and Dennett, there is a strong sense that the whole of a thing is nothing more than the sum of its parts and that emergent level entities and explanations farcical.[10] It is no accident that there is a strong tie between reductionist accounts of emergence and avowed atheism, as the work of both Dawkins and Dennett exemplifies.
[1] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 689.
[2] Ernst Mayr, Toward a New Philosophy of Biology: Observations of an Evolutionist (Cambridge: Harvard University, 1988), 15.
[3] Harold Morowitz, The Emergence of Everything: How the World Became Complex, (New York: Oxford University, 2002), 20.
[4] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 693-695.
[5] Arthur Peacocke, “The Sound of Sheer Silence,” in Neuroscience and the Person: Scientific Perspectives on Divine Action, ed. Robert J. Russell, Nancey Murphy, Theo C. Meyering, and Michael Arbib (Notre Dame: University of Notre Dame, 1999), 225–226.
[6] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 702.
[7] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 705.
[8] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 706.
[9] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 709.
[10] Gregory R. Peterson, Species of Emergence, Zygon 41, no. 3, 700.