The Routledge Handbook of Emergence

Sophie Gibb, Robin Findlay Hendry, Tom Lancaster

• Publisher: Routledge
• Year: 2019
• ISBN:
  9781317381495
• Edition: 1
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

Emergence is often described as the idea that the whole is greater than the sum of the parts: interactions among the components of a system lead to distinctive novel properties. It has been invoked to describe the flocking of birds, the phases of matter and human consciousness, along with many other phenomena. Since the nineteenth century, the notion of emergence has been widely applied in philosophy, particularly in contemporary philosophy of mind, philosophy of science and metaphysics. It has more recently become central to scientists' understanding of phenomena across physics, chemistry, complexity and systems theory, biology and the social sciences.

The Routledge Handbook of Emergence is an outstanding reference source and exploration of the concept of emergence, and is the first collection of its kind. Thirty-two chapters by an international team of contributors are organised into four parts:

• 
  
  

• Foundations of emergence
• Emergence and mind
• Emergence and physics
• Emergence and the special sciences

Within these sections important topics and problems in emergence are explained, including the British Emergentists; weak vs. strong emergence; emergence and downward causation; dependence, complexity and mechanisms; mental causation, consciousness and dualism; quantum mechanics, soft matter and chemistry; and evolution, cognitive science and social sciences.

Essential reading for students and researchers in philosophy of mind, philosophy of science and metaphysics, The Routledge Handbook of Emergence will also be of interest to those studying foundational issues in biology, chemistry, physics and psychology.

Part 1
Foundations of emergence

1
British Emergentism

Brian P. McLaughlin

The endeavor to understand the natural world through scientific enquiry, while having proved enormously successful, has resulted in numerous sciences. Taking the widest divisions, there is physics and then there are the special sciences, which include, among others, chemistry, biology, psychology, linguistics, sociology, and economics. There are, moreover, many divisions within these broad cuts, including within physics. To be sure, one of the main aims of scientific theorizing is unification, but though science unifies, it also diversifies. As Jerry Fodor once remarked, “[T]he development of science has witnessed the proliferation of specialized disciplines at least as often as it has witnessed their elimination” (1975, 9–10) or, we may add, their unification. This bodes well for employment in science, at least if adequate funding is available. Still, though, the Milesian longing for a comprehensive, systematically unified, final scientific theory of the natural world persists, and indeed is a driving force for some physicists.

Let us step back from this situation, draw a circle around it, and ask: Given that there is one and only one natural world that the enterprise of science seeks to understand, why are there many sciences rather than just one science? There is no received answer. The factors that immediately come to mind are many and varied. To name just a few: there are, arguably, scientific unifications yet to be achieved; but also, different sciences serve different specific purposes; they can deploy different methods; different concepts can cross-classify the same phenomena; there is computational intractability; and there are limitations on our ability to theorize imposed by our cognitive architecture, including, arguably, gaps in our conceptual schemes that we are constitutionally unable to build conceptual bridges to close. However, our scientific to-do lists, our aims, our methods, our built-in cognitive limitations, and other factors concerning us aside, does the natural world at least in principle admit of a comprehensive, systematically unified, final scientific theory?

In this chapter, I discuss the British Emergentist movement, a movement that presented a view of the natural world according to which the answer is “no.” Although it has ancient roots (Caston 1997), the movement began around the mid-nineteenth century and flourished in the first quarter of the twentieth century (McLaughlin 1992). The truly major works in the movement are John Stuart Mill’s System of Logic (the first edition of which was published in 1843, and the eighth edition of which was published in 1872), Samuel Alexander’s two-volume Space, Time and Deity (1920), Lloyd Morgan’s Emergent Evolution (1923), and C.D. Broad’s The Mind and Its Place in Nature (1925), but other notable works include Alexander Bain’s Logic (1870) and George Henry Lewes’s two-volume Problems of Life and Mind (1875).

A view can be found in these works according to which there are many sciences rather than just one science, because of the way the natural world itself is. In its mature form in Alexander (1920), Morgan (1923), and Broad (1925), the view is that the natural world is layered: it has a hierarchical structure in which higher tiers are dependent on, but are not reducible to, lower tiers. The elements of higher tiers are wholes or systems entirely composed of elements of lower tiers, but possessed of the kinds of properties not possessed by any of their constituents, properties that emerge from their constituents being propertied and related in certain ways. The properties of wholes that so emerge are thereby emergent properties. Such emergent properties figure in fundamental laws of nature.

On this view of the nomological structure of the natural world, there is a vast collage of fundamental laws. The natural world is thus such that the Milesian longing for a comprehensive, small group of systematically integrated fundamental laws cannot be satisfied. Broad quipped, adding a spoonful of sweetness to help the medicine go down, that if there is indeed such a lack of unity in the natural world, it “must simply be swallowed whole with that philosophical jam that Professor Alexander calls ‘natural piety’” (1925, 55).

In what follows, I first lightly sketch the history of the British Emergentist movement from Mill to Broad, with a focus just on the issue of why there are many sciences.¹ Then, I briefly address the issue of whether there are emergent properties in the sense in question. I conclude with a few remarks about appeals in contemporary physics to a different notion of emergence.

In A System of Logic (Book III, Ch. VI), Mill distinguishes “two modes of the conjoint action of causes, the mechanical and the chemical” (1868, Seventh Edition, xvi). He tells us that causes combine in the mechanical mode to produce an effect just in case that effect is the result of their conjoint action and the sum of what would have been the effects of each of the causes had they acted alone. He illustrates this mode with the example of forces acting jointly to produce a certain movement. The resulting movement is the vector sum of what would have been the effects of each of the component forces had they acted alone. Citing “the principle of the Composition of Forces in mechanics,” Mill says that “in imitation of that well-chosen name,” he gives “the name of the Composition of Causes to the principle which is exemplified in all cases in which the joint effect of several causes is identical with the sum of their separate effects” (406). The principle of the Composition of Causes, he tells us, “by no means prevails in all departments of the field of nature” (406). Often, causes combine instead in the chemical mode, so-called because it is exhibited in chemical interactions, though by no means exclusively in such interactions. Causes combine in the chemical mode to produce an effect just in case the effect is the result of their conjoint action and not the sum of what would have been the effect of each of the causes had they acted alone. The product of a chemical process is in no sense the sum of the effects of each reactant. Combining methane and oxygen, for instance, produces carbon dioxide and water, which is in no sense the sum of what would have been the effects of methane and oxygen acting alone. Given that an effect of the causes that act together to produce it either will be the sum of what would have been the effects of each cause acting alone or it will not be, the distinction is exhaustive: causes combine either in the mechanical mode or in the chemical mode with respect to any effect that results just from their conjoint action. This distinction, Mill tells us, is “one of the most fundamental distinctions in nature” (409).

According to Mill, sciences strive to offer deductive explanations of phenomena in terms of laws, and so deductive nomological explanations. But there is no single science, since sometimes when the principle of the Composition of Causes fails, “the concurrence of causes is such as to determine a change in the properties of the body generally, and render it subject to new laws, more or less dissimilar to those to which it conformed in its previous state” (413). On his view, we have special sciences because

at some particular points in the transition from separate to united action, the laws change, and an entirely new set of effects are either added to, or take the place of, those which arise from the separate agency of the same causes: the laws of these new effects being again susceptible of composition, to an indefinite extent, like the laws which they superseded.

(411) ²

Consider, for instance, organic bodies. They are wholly composed of kinds of ingredients that also figure as ingredients of inorganic matter, but causal factors have brought entities of these kinds together into an organization, a whole or system or complex body, that exhibits new properties, properties that figure in laws of physiology. Those laws are not deducible from the laws concerning the ingredients as they occur in inorganic matter. Moreover, the laws of physiology in question supersede them. As concerns bodies that are ingredients of inorganic matter and come together to make up organic bodies, he says: “Those bodies continue, as before, to obey mechanical and chemical laws, in so far as the operation of those laws is not counteracted by the new laws that govern them as organized beings” (409).

In Mill’s view, sciences are nomothetic, but the natural world is not governed by a small group of systematically, well-integrated fundamental laws. It is governed by a collage of fundamental laws, with laws concerning complex organizations superseding laws concerning their constituents in isolation. The various departments of science are concerned with the various compartments of nature.

Mill’s distinction between the mechanical and the chemical modes of the conjoint action of causes ignited the British Emergentist movement. Mill himself, however, never used the term “emergence.” He called effects of causes acting conjointly in the mechanical mode, “homogeneous” effects (412); those of causes acting conjointly in the chemical mode, “heterogeneous” effects; and the laws governing the latter causal transactions, “heteropathic laws” (409). George Henry Lewes (1875) called Mill’s heterogeneous effects “emergents” and his homogeneous effects “resultants.” Effects are either resultants or emergents. An emergent, Lewes tells us, “is unlike its components insofar as these are incommensurable, and it cannot be reduced to their sum or their difference” (1875, 412). Given that, the first occurrence of each kind of emergent is taken to introduce genuine novelty into the world. Lewes’s talk of emergents led to talk of emergence in the work of Alexander, and Morgan and Broad followed Alexander in this. These theorists took chemical substances and organic bodies to be wholly composed of atoms and subatomic particles (they knew about electrons and protons), and so took changes to involve rearrangements of atoms and more fundamental particles. But they held that new configurations of them can possess genuinely novel, and indeed irreducible, properties. Their works inspired a large, international literature, both supportive (see, e.g., Lovejoy 1927) and critical (see, e.g., Pepper 1926).³

The idea that the natural world has a hierarchical structure is first explicitly articulated in the British Emergentist literature in Alexander’s Space, Time, and Deity. Alexander writes of the emergence of new qualities from the complexity of organization, telling us:

The emergence of a new quality from any level of existence means that at that level there comes into being a certain constellation or collocation of the motions belonging to that level, and this collocation possesses a new quality distinctive of the higher-complex.… The higher-quality emerges from the lower level of existence and has is roots therein, but it emerges therefrom, and it does not belong to that lower level, but constitutes its possessor a new order of existent with its special laws of behavior. The existence of emergent qualities thus described is something to be noted, as some would say, under the compulsion of brute empirical fact, or, as I should prefer to say in less harsh terms, to be accepted with the “natural piety” of the investigator. It admits of no explanation.

(1920, 45–47)

Although existents at higher levels are dependent on existents at lower levels in that they are wholly composed of such existents, the higher-level existents have emergent qualities and are governed in part by autonomous laws of behavior that cite those qualities.

If Alexander’s hierarchical view of the natural world is correct, then the goal of finding a small group of systematically, well-integrated fundamental laws of nature that govern the entire natural world is a pipe dream. The cure for the Milesian longing is a large dose of natural piety.

In Emergent Evolution, Morgan embraced Alexander’s view of ascending levels of reality and proposed an evolutionary cosmology inspired by Alexander’s claim that Darwin’s principle of adaptation extends “below the level of life” (Alexander 1920, Vol. 2, 310). As concerns the ascending levels or grades of reality, Morgan says there are

physical and chemical events in progressively ascending grades. Later in evolutionary sequence life emerges – a new “quality” of certain material or physico-chemical systems with supervenient[⁴] vital relations hitherto not in being. Here again there are some progressively ascending grades. Then within this organic matrix, or some highly differentiated part thereof, already “qualified”… by life, there emerges the higher quality of consciousness or mind.

(1923, 9–10)

As concerns the evolution of the ascending grades, Morgan says:

At any emergent stage of evolutionary progress is a new kind of relatedness… hitherto not in being. In virtue of such new kinds of relatedness, not only have natural entities new qualities within their own proper being, but new...

Table of contents

• Cover
• Half Title
• Series Page
• Title
• Copyright
• CONTENTS
• Notes on contributors
• Acknowledgements
• Introduction
• PART 1 Foundations of emergence
• PART 2 Emergence and mind
• PART 3 Emergence and physics
• PART 4 Emergence and the special sciences
• Index