2.1 Metaphysical Emergence and Homeostatic Organization

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In the previous chapter, the attempt was made to show that the processes

in which the components of an organismic hierarchy are engaged produce

homeostasis through abilities to exchange data internally, selectively

convert data to information, integrate that information, and process information

from environments. Now, it will be argued that the components

and attending processes of an organism should be considered as emergent

phenomena because of the way in which the components are organized

to maintain the homeostasis of the organism at the various levels in the

organismic hierarchy (also see Arp, 2008a).

Near the end of the fi rst section of the previous chapter, the claim was

made that higher level subsystems are the phenomena that literally emerge

from lower level subsystems and processes of an organism conceived of as

a hierarchically organized living entity. With respect to organisms and the

descriptions of their components, processes, and properties, I endorse

certain forms of metaphysical and epistemological emergence. As Silberstein

(2002), Silberstein & McGreever (1999), and McLaughlin (1992, 1997)

have clarifi ed, there are metaphysical and epistemological forms of emergence.

In Kim’s (1995, p. 224) words, according to metaphysical emergentists,

“a property of a complex system is said to be ‘emergent’ just in case,

although it arises out of the properties and relations characterizing simpler

constituents, it is neither predictable from, nor reducible to, these lowerlevel

characteristics” (also see the discussions in Kim, 1999; Wimsatt, 1994,

1997; Emmeche, Køppe, & Stjernfelt, 2000; Craver, 2001; Lowe, 2000;

O’Connor, 1994; Rueger, 2000; Zylstra, 1992). According to epistemological

emergentists, the concepts, theories, models, or frameworks we utilize

to describe phenomena at a certain level are nonreducible to the concepts,

theories, and so forth at a lower level (see, e.g., the discussions in Batterman, 2001; Cartwright, 1999; Primas, 1998; Sklar, 1999; Dupré, 1993;

Crane, 2001; Van Gulick, 2001).

Further, as Silberstein (2002) and Silberstein & McGeever (1999) clarify,

within the genus of metaphysical emergence, four kinds have been distinguished,

namely, non-elimination, nonidentity, mereological emergence,

and nomological emergence. Also, within the genus of epistemological

emergence, at least two kinds of approaches have been distinguished,

namely, predictive/explanatory emergence and representational/cognitive

emergence. In light of the previous chapter, the metaphysical and epistemological

forms of emergence that will be explored and defended in this

chapter are the following: nomological emergence, understood by Silberstein

(2002, p. 91) as “cases in which higher-level entities, properties, etc., are

governed by higher-level laws that are not determined by or necessitated

by the fundamental laws of physics governing the structure and behavior

of their most basic physical parts,” and representational/cognitive emergence,

understood by Silberstein (2002, p. 92) as the thesis that “wholes (systems)

exhibit features, patterns or regularities that cannot be fully represented

(understood) using the theoretical and representational resources adequate

for describing and understanding the features and regularities of their more

basic parts and the relations between those more basic parts.”

From the metaphysical perspective, nomological emergentists deny the

general principle that the whole can be accounted for fully in terms of the

physical parts, and so their view is contrasted with nomological reductionism.

According to nomological reductionists, there are really no entities,

properties, or substances that arise out of more fundamental physical

ones, since, once the more fundamental ones have been described, that

is all there is to the reality of an entity, property, or substance. Thus, for

example, when people speak about water, they may take it to be a substance

in its own right. However, according to the nomological reductionist,

water just is hydrogen and oxygen—nothing new emerges when two

hydrogen molecules combine with one oxygen molecule. Conversely,

according to a nomological emergentist, there is something about water—

for example, its liquidity or liquid property—that emerges from the hydrogen

and oxygen molecules, making it such that this liquidity exists on a

separate metaphysical plane from the molecules on which it depends.

After all, reason nomological emergentists, liquidity appears to be something

distinct from hydrogen and oxygen molecules, as well as their

chemical bond.

From the epistemological perspective, representational emergentists are

contrasted with representational/theoretical reductionists, who attempt to reduce concepts, theories, and so forth to their lowest common

denominator, as it were, and this usually means a description in terms

of physicochemical entities, properties, or substances and their attending

laws or principles. Thus, if we took the cell as an example, according

to a representational reductionist, the cell can be described completely

within a physicochemical framework of concepts, theories, models, laws,

and so forth associated with vectors and physical substructures and

bonds (see the discussions in Churchland, 1995; Humphreys, 1997;

Primas, 1998).

Some emergentists maintain that chemical bonds or basic physical

structures—as well as our descriptions of them—are nonreducible to the

molecules and atoms of which they are composed. Thus, there is an

emergence–reduction divide even at the physicochemical level (see, e.g.,

the discussions in Hendry, 1999; Hellman, 1999; Belot & Earman, 1997).

This physicochemical debate is avoided here, and instead I want to maintain

that starting with the organelles that constitute a cell, and continuing

up the hierarchy of components in processes and subsystems of an organism—

including psychological phenomena—we have clear instances of

emergent phenomena. The fundamental reason why these components

and their attending processes must be considered as emergent phenomena

has to do with the way in which the components are organized to

function so as to maintain the homeostasis of the organism at the various

levels in the hierarchy. I will refer to this position as the homeostatic

organization view (HOV) of biological phenomena. Since homeostasis

is ubiquitous as both a concept and as a recognized reality in biological,

psychological, and philosophical communities (among many other disciplines),

it makes for a natural point of discussion in the emergence/reduction

debate.

In the fi rst section of the previous chapter, a distinction was drawn

between particularized homeostasis and generalized homeostasis. It was

shown that because the various processes and subsystems of an organism

are functioning properly in their internal environments (particularized

homeostasis), the organism is able to live its life effectively in some environment

external to it (generalized homeostasis). Here, the very existence

of components and their activities at various levels in the organism’s hierarchy

is linked to the coordination of such components so as ultimately

to produce generalized homeostasis. The components of an organism are

organized in such a way that the resultant outcome of their processes becomes

fi rst particularized homeostasis and then generalized homeostasis.

That components are organized to perform some function resulting in homeostasis is one feature that marks them out to be novel emergent

entities distinguishable from the very physicochemical processes of which

they are composed.

It was noted already that homeostasis fi rst occurs at the basic level of

the organized coordination of the activities of organelles in a cell. Researchers

like Audesirk et al. (2002), Kandel et al. (2000), Voet et al. (2002),

Campbell & Reece (1999), and Smolensky (1988) document cellular homeostasis.

At this basic level of organelle interaction within the cell, we also

would have the fi rst instances of salient emergent biological properties that

are distinct from the physicochemical properties upon which they depend.

Consider all of the information being exchanged between and among the

organelles of an animal cell. The nucleus is in constant communication

with each mitochondrion, centriole, golgi apparatus, ribosome, and endoplasmic

reticulum, each of which has its own function in maintaining the

overall homeostasis of the cell (see fi gure 2.1): the nucleus contains the

nucleolus and houses DNA, the mitochondrion supplies the cell with

energy, centrioles are important for cell division, the Golgi apparatus stores

Ribosomes

Endoplasmic

Reticulum

Nucleus

Nucleolus

Centriole

Golgi

Apparatus

Plasma

Membrane

Mitochondrion

Figure 2.1

The major organelles of the animal cell proteins, ribosomes are the sites for protein synthesis, the endoplasmic

reticulum expedites the transport of cellular material, and the plasma

membrane permits materials to move into and out of the cell.

In fact, components of organisms as they have been described—

organelles, cells, organs, and subsystems, as well as the organism itself—all

would be considered emergent entities. Referring to the schematization

of an organism as one huge triangle containing smaller triangles that was

used in fi gure 1.1 of the previous chapter, each one of those triangles—

from biggest to smallest—represents a biologically emergent phenomenon.

For example, although the organelles of a cell themselves are made up of

physicochemical entities, they engage in coordinated kinds of activities

that benefi t the overall homeostasis of the cell; so too, although kidney

cells are made up of organelles—which are made up of physicochemical

entities—the kidney cells themselves engage in coordinated activities that

benefi t the homeostasis of the kidney; and so on, up the hierarchy of the

mammal. This point was reiterated in my discussions with Jerry Morrissey

at his lab at Washington University in St. Louis, where Morrissey conducts

research on kidney cells (see the fi nal section of Kaneto, Morrissey,

McCracken, Reyes, & Klahr, 1998).

Now, in arguing for HOV, I am not advocating some “spooky stuff”

principle (this terminology is borrowed from Churchland, 1993) of internal

“vitalism” or external “design,” the likes of which might be put forward

by an organicist or a creationist (also see Arp, 1998, 1999, 2002). As was

mentioned in the last chapter, the property of internal–hierarchical data

exchange in an organism manifests upward causation, whereby the lower

levels of the hierarchy exhibit causal infl uence over the higher levels.

Likewise, the dual properties of data selectivity and informational integration

manifest downward causation, whereby the higher levels of the hierarchy

exhibit causal infl uence over the lower levels, in terms of control.

Consider that an organism like the human body is a complex multicllular

entity made up of levels of independently organized entities

that perform certain operations. These organized entities are hierarchically

arranged from organ systems (e.g., the nervous system), composed of

organs (brain, spinal cord, etc.), that are composed of tissues (nervous

tissue), which are composed of cells (neurons, glial cells), each of which is

composed of organelles (mitochondrion, nucleus, etc.), that are composed

of organic molecules (carbon, nitrogen, oxygen, DNA, etc.). Each of these

entities functions such that the operations at the lower levels contribute

to the emergence of entities and their operations at the higher levels.

Because of the activities of organic molecules, it is possible for organelles and their attending activities at a higher level to emerge, and because of

the activities of organelles, it is possible for cells and their attending activities

at a higher level to emerge, and so on.

Now, think of all of the complex upward and downward causal relations

taking place when the human body simply gets up out of bed. Put crudely,

the brain must exhibit downward causation, as a necessary condition,

upon its own neurochemical constituents in order to cause the body to get

up, while the neurochemical constituents must exhibit upward causation,

as a necessary condition, for movement to occur in the fi rst place. There

is no “spooky” vitalism or design in any of this upward and downward

causal interaction.

In fact, HOV provides an important addition to one standard interpretation

of a hierarchical mechanism. In philosophy of science and philosophy

of mind literature, it is now commonplace to fi nd references to Craver’s

(2001) Cummins-infl uenced description of a mechanism hierarchy as some

mechanism S, which is -ing, composed of smaller entity Xs, which are

-ing. These Xs are little mechanisms themselves consisting of smaller

entity Ps, which are -ing (also see Machamer, Darden, & Craver, 2000).

This view has the benefi t of describing some mechanism as a hierarchically

organized system, in a nonspooky fashion, consisting of entities engaging

in inter- and intraleveled causally effi cacious activities. Also, this view is

specifi cally supposed to account for living mechanisms, which classically

have resisted a mechanistic description. In fact, Craver’s view of a hierarchical

mechanism maps onto my schematization of a hierarchically organized

system schematized as nested triangles, and our two views have

much in common.

However, as I pointed out to Carl Craver at a conference at Washington

University in St. Louis, the problem with his view of mechanisms is that

it neglects the more specifi ed kinds of organized homeostatic activities in

which the processes of organismic hierarchies are engaged. It is arguable

that physicochemical entities—the so-called smaller entity Ps, which are

-ing, that make up the organelles, which are -ing—themselves are not

coordinated in such a way so as to produce homeostatic results; they are

not organized to do something, or achieve some result in this homeostatic

manner. Further, it is arguable that physicochemical entities are not

organized in hierarchical ways such that we could say they are engaged

in particularized homeostatic processes contributing to a generalized

homeostasis.

Organisms are responsive to their environments in such a way that they

can adapt to changes. A callous on your foot is a simple example of the integumentary subsystem of your body adapting to a change in its external

environment. Organisms, as well as the subsystems and processes of which

they are composed, exhibit a certain amount of fl exibility and malleability

in relation to their internal and external environments. In fact, as we have

already seen, the subsystems and processes of organisms produce particularized

and generalized homeostasis, namely, a relatively constant coordination

among the components of an organism, given the interaction

of these components with environments internal to and external to the

organism. Homeostasis and adaptability are two sides of the same coin. As

was intimated already, this property of adaptability in relation to environments

is yet another essential feature that distinguishes living entities,

properties, or substances from nonliving ones. Another way to say this is

that the adaptability of processes and subsystems in organisms can be

pointed to as a clear way in which to distinguish the biological from the

physicochemical realms.

Consider a rock. A rock would be classifi ed as a nonliving, physicochemical

entity because it does not have this ability to adapt to environments

and situations the way that living, biological entities do. If a rock

is hit by a hammer with a certain amount of force, it breaks up into

pieces, the pieces fall where they may according to physicochemical laws,

and that is the end of the story—this is its “response” to the environment.

Alternatively, if one’s forearm is hit by a hammer such that a bone

breaks, the various systems of the body go to work to repair the damage

so that some form of homeostasis can be reachieved. The body adaptively

responds to this environmental pressure, and the hierarchy goes to work

on fi xing the problem. Further, if the bone does not heal correctly or the

muscles surrounding it have atrophied because of the blow, the subsystems

and processes of the body can compensate for the injury. If the hierarchy

cannot fi x the problem, it adjusts or readjusts if necessary.

Homeostasis in an organism entails adaptability as a necessary condition,

for it is the organism’s response to its ever-changing environment that

will occasion the need for either particularized or generalized homeostasis.

Of course, biological entities are constructed of physicochemical components

and are subject to the same physicochemical laws as any other

piece of matter in the world; again, there is upward physicochemical causation

that acts as a necessary condition for biological functioning.

However, biological entities, as hierarchically organized living systems,

have this distinguishing property whereby the subsystems and processes

adaptively respond to their environments in ways that other physicochemical

entities do not.