Van Huyssteen J.W. (editor) Encyclopedia of Science and Religion

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LIFE,BIOLOGICAL ASPECTS

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van Baaren. Th. P. “Death.” In Death, Afterlife, and the

Soul, ed. Lawrence E. Sullivan. New York and Lon-

don: Macmillan, 1989.

van Uytfanghe, M. “Platonisme et eschatologie chrétienne:

Leur symbiose graduelle dans les Passions et les

panégyriques des martyrs et dans les biographies

spirituelles (IIe–VIe s.).” In Fructus centesimus:

Mélanges offerts à Gerard J. M. Bertelink à l’occasion

de son soixante-cinquième anniversaire, eds. A. A. R.

Bastiaensen, A. Hilhorst, and C. H. Kneepkens. Dor-

drecht, Netherlands: Kluwer, 1989.

van Uytfanghe, M. “Platonisme II.” In De Tertullien aux

Mozarabes: Mélanges offerts à Jacques Fontaine, à l’c-

casion de son 70e anniversaire, 3 vols., eds. Louis

Holtz and Jean-Claude Fredouille. Paris: Institut d’é-

tudes augustiniennes, 1992.

Walker, Daniel Pickering. The Decline of Hell: Seventeenth-

Century Discussions of Eternal Torment. Chicago:

University of Chicago Press, 1964.

JAN BREMMER

LIFE,BIOLOGICAL ASPECTS

Biologically, life, as contrasted with death or with

nonliving objects, is an evident fact but difficult to

characterize precisely. Living organisms are self-

maintaining systems; they grow and are irritable in

response to stimuli. They resist dying. They repro-

duce. The developing embryo is especially im-

pressive. Organisms post a defended, semiperme-

able boundary between themselves and the

outside world; they assimilate environmental mate-

rials to their own needs. They can be healthy or

diseased. Some accounts claim that the minimal

form of autonomy necessary and sufficient for

characterizing biological life is what is termed au-

topoiesis, literally self-making. Some defense of a

“self” (a somatic self, having to do with the body,

rather than a psychological self) is thus required.

Living organisms gain and maintain internal

order against the disordering tendencies of exter-

nal nature. They keep recomposing themselves,

while inanimate things run down, erode, and de-

compose. Organisms pump out disorder. Life, as

physicist Erwin Schrödinger notes in his 1945

work, What is Life?, is a local countercurrent to en-

tropy, an energetic fight uphill in a world that over-

all moves thermodynamically downhill.

The organism as system

The constellation of these characteristics is

nowhere found outside living organisms, although

some of them can be mimicked or analogically ex-

tended to products designed by living systems,

such as computers, and some are found in sponta-

neous abiotic nature. A crystal reproduces a pat-

tern and may restore a damaged surface; a plane-

tary system continues in an equilibrium; a volcano

may grow in countercurrent to entropy. A lenticu-

lar altocumulus cloud, formed as a standing wave

over a mountain range, is steadily recomposed by

input and output of air flow. A target-seeking mis-

sile adjusts its course by environmental feedback.

Computers are cognitive processors and can be

running well or poorly.

The know-how for life is coded into genetic

sets, which are missing in minerals, volcanoes,

clouds, computers, and target-seeking missiles. An

organism is thus a spontaneous cybernetic system,

self-maintaining with a control center, sustaining

and reproducing itself on the basis of information

about how to make its way through the world.

There is some internal representation that is sym-

bolically mediated in the coded “program” and me-

tabolism executing this goal, a checking against

performance in the world, using some sentient,

perceptive, or other responsive capacities by

which to compare match and mismatch. On the

basis of information received, the cybernetic sys-

tem can reckon with vicissitudes, opportunities,

and adversities that the world presents.

Organisms employ physical and chemical

causes, but, distinctive to life, there is “informa-

tion” superintending the causes. This information

is a modern equivalent of what Aristotle (384–322

B.C.E.) called formal and final causes; it gives the

organism a telos, or end, but not always a felt or

conscious end-in-view. Formerly, biologists looked

for entelechy, some distinctive component in or-

ganisms not found in merely physicochemical sys-

tems. Although entelechy was never found, the

major discovery of biologists in the last half cen-

tury has been massive amounts of information

coded in DNA, a sort of linguistic molecule.

Living organisms impose a code on four nu-

cleotide bases strung as cross links on a double

helix. A triplet of bases stands for one of the

twenty amino acids, and by a serial “reading” of

the DNA, “translated” by messenger RNA, a long

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polypeptide chain is synthesized, such that its se-

quential structure predetermines the bioform into

which it will fold. Ever-lengthening chains are or-

ganized into genes. Diverse proteins, lipids, carbo-

hydrates, enzymes—all the life structures—are thus

“written into” the genetic library.

The DNA representing life is thus, to continue

analogies, a “cognitive set,” not less than a biolog-

ical set. Organisms use these molecular positions

to code the information necessary for life. In this

sense, the genome is a set of conservation mole-

cules. The novel resourcefulness lies in the epis-

temic content conserved, developed, and thrown

forward to make biological resources out of the

physicochemical sources. The presence of this ex-

ecutive program is often said to be cybernetic, a

word recalling a governor or helmsman. An open

cybernetic system is partly a special kind of cause

and effect system, partly a historical information

system discovering and evaluating ends so as to

map and make a way through the world, and

partly a system of significances attached to opera-

tions, pursuits, resources.

Threshold of life

DNA codes a life that is carried on not merely at

the level described above, but at the environmen-

tal, phenotypical level. What occurs at the level of

molecular biology manifests itself, via a compli-

cated translation and interaction from genotypic to

phenotypic levels (i.e., from the microscopic level

of the genes to the macro level of the whole or-

ganism). This translation occurs at the native

ranges, where such life is selected for or against as

it is defended in its environment. With this process

in mind some analysts to define as alive whatever

is subject to natural selection, thus presuming also

mutation. These features typically do characterize

life. Critics of this definition respond that some

things (such as viruses or groups of organisms) are

subject to natural selection but are not alive. Also,

life sometimes continues with much reduced natu-

ral selection. This is seen in human in their cultural

environment. This phenomenon is also witnessed

in clonal organisms that are all genetically identical

or in relatively constant environments where most

genetic changes result from mutations that are cat-

egorized as drift (i.e., functional changes that neu-

tral to survival, neither beneficial nor detrimental).

Various thresholds or borderlines of life are

disputed. A person may be considered “brain

dead,” although somatically the heart is still beat-

ing (often with a mechanical respirator). Many bi-

ologists hold that viruses are not (fully) alive, but

are anomalous self-reproducing DNA fragments

that parasitize living cells, largely borrowing most

of their vital metabolisms from the host cell.

Viruses are not self-contained, not cellular, but

must be contained within other selves and cells.

Computer advances have raised the possibility of

“artificial life,” with debates about what would

count as a living computer, or perhaps as a living

program, within a computer. Some organic mole-

cules are known from space, but no extraterrestrial

life is yet known. Scientists, philosophers, and the-

ologians speculate, often intensely, about whether

such life is likely to be present.

See also LIFE, RELIGIOUS AND PHILOSOPHICAL ASPECTS;

IFE SCIENCES

Bibliography

Kauffman, Stuart A. The Origins of Order: Self-

organization and Selection in Evolution. Oxford:

Oxford University Press, 1993.

Maturana, Humberto R., and Varela, Francisco J. Au-

topoiesis and Cognition: The Realization of the Living.

Dordrecht, Netherlands, and Boston: D. Reidel, 1980.

Maynard Smith, John, and Szathmáry, Eörs. The

Origins of Life. Oxford: Oxford University Press,

1999.

Rosen, Robert. Life Itself: A Comprehensive Inquiry into

the Nature, Origin, and Fabrication of Life. New

York: Columbia University Press, 1991.

Schrödinger, Erwin. What Is Life? Cambridge, UK: Cam-

bridge University Press, 1945.

HOLMES ROLSTON, III

LIFE,ORIGINS OF

Fossilized microbes or their chemical traces have

been found in the oldest rocks on Earth. These

rocks, which are about 3.8 billion years old, draw

a picture of the structurally complex and metabol-

ically sophisticated microbiota that already existed

at that time. This leaves for the emergence of living

things on Earth only a relatively short period of

less than three hundred million years. During that

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period, complicated metabolic pathways must

have developed. How?

Many religious as well as philosophical ideas

assume that the interference with matter by a cre-

ative force or a creator results in the appearance of

self-replicating life. Often the teleological character

of living things in combination with a lack of un-

derstanding of natural processes leads to the con-

clusion that life is, in principle, “not of this world.”

In contract, the materialistic philosophical tradition

interprets life as the most refined form of self-or-

ganizing matter.

It is an enormous intellectual challenge to ex-

plain the transition from lifeless chemistry to biol-

ogy. The possible scenarios for this transition push

scientific theories, worldviews, and the imagina-

tion to their limits. The following questions need to

be answered. How is it possible that the beautifully

well-balanced and encapsulated web of interaction

that constitutes a living cell arose unintended from

abiotic building blocks? How did its metabolism

evolve? How could it happen that all the informa-

tion that a parent cell needs to reproduce itself in

the form of progeny was written in the chemical

letters of the DNA molecule? And what was the

first step that linked information (DNA) to function

(proteins)? None of these questions has yet been

answered by experimental evidence, however, nu-

merous theories propose plausible scenarios that

could result in the appearance of all living things.

In addition, chemists have recreated chemical re-

actions that result in the formation of numerous of

the most essential organic building blocks, such as

amino acids and nucleic acids. Chemists have so

far failed, however, to reconstruct the abiological

formation under prebiotic conditions of the mole-

cule ribose, which is essential to life as the back-

bone of DNA and RNA molecules. It has also been

shown that amphiphilic compounds, such as fatty

acids, spontaneously self-assemble and form en-

capsulated spheres, which separate into an “inside”

from an “outside,” and thus represent the origin of

compartimentation. The most prominent of theo-

ries about the origin of life will be presented in this

entry, and some of the problems related to the

models will be discussed.

The Oparin-Haldane model

The Oparin-Haldane model of prebiotic evolution

and cell formation was developed independently

during the 1920s by British biologist J. B. S. Hal-

dane and Soviet biochemist Aleksandr Oparin. Ac-

cording to the Oparin-Haldane model, organic

molecules were formed in the reducing atmos-

phere of the early Earth and then accumulated in

the oceans, where a thin organic solution, the so-

called primordial soup, formed. In addition to the

atmospheric source of organics, the theory also

considers input from comets and certain types of

meteorites as an important source of organic build-

ing blocks.

In the primordial soup, amphiphilic mole-

cules, such as fatty acids, continuously formed

small fatty droplets called coacervates. During self-

assembly these coacervates encapsulated a small

amount of the soup, which supplied them with

building blocks and energy sources. Further coac-

ervates grew by incorporation of more am-

phiphilic compounds until they became large

enough to be unstable, resulting in coacervate di-

vision. Even during the coacervate state, competi-

tion and selection among these structures were

driving a progressive evolution. The Oparin-Hal-

dane model assumed that the original way of feed-

ing was heterotrophic, which means that the cel-

lular structures grew by assimilation of

prefabricated organic building blocks that also

served as energy sources. Overall, the model sup-

poses that cells came first, proteins second, and

genes third.

The major contribution of the Oparin-Haldane

model to the scientific origin of life debate was to

link abiotic chemistry to the history of life. Haldane

and Oparin broke with the powerful and experi-

mentally supported paradigm of the French

chemist Louis Pasteur that only life can be the

source of new life and that life can not arise spon-

taneously from a nonliving material. Despite its

narrative eloquence, the Oparin-Haldane model

has serious scientific shortcomings: (1) The atmos-

phere of the early Earth was most likely different

and less reduced than the Oparin-Haldane model

requires for the synthesis of all the molecules nec-

essary for prebiotic synthesis; (2) The intensity of

ultraviolet radiation on the surface of the ocean

would have constrained the accumulation of prebi-

otic molecules. In addition, complex molecules are

less stable when dissolved in water, which seri-

ously limits the formation of information and func-

tion-carrying macromolecules like RNA, DNA, and

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proteins; and (3) Prebiotic synthesis produces only

small amounts of the desired organic compounds.

Template-based models

Clay-based template. Some scientists have pro-

posed alternatives to the primeval soup model that

can be summarized as template-based origin of life

models. One of them, the clay-based origin of life

theory, attributes to microcrystals of clay both an

informational and a catalytic function. According

to the theory, the matrix of clay contains a regular

array of ionic sites, which are occupied by irregu-

larly alternating patterns of metal ions such as

magnesium or aluminum. The pattern of alternat-

ing metal ions contains information similar to the

patterns of nucleic acids in DNA or RNA mole-

cules. Organic molecules, which are present in the

environment of clay crystals, may have been at-

tracted by the electrostatic potential of the metal

ions and positioned themselves in a way that fa-

cilitates a chemical reaction between the adsorbed

molecules (i.e., those attached to the surface). In

this scenario, clay surfaces have a catalytic func-

tion comparable to those of proteins. The infor-

mation content of clay crystals was transferred to

a new generation of crystals by accreting silicate

and metals from the surrounding water and by re-

producing the original pattern of metal ions asso-

ciated with the new clay matrix. It may be that

clay-based life existed for millions of years but

was finally out-competed by RNA-based life,

which had much better chemical properties, and

all traces of these original clay-based life forms

disappeared.

The clay model has two major strengths: (1) A

variety of clays do in fact catalyze the polymer-

ization of organic compounds under conditions

that are realistic for the early Earth; (2) Stereospe-

cific amino acid binding and polymerization have

been demonstrated. Among several weaknesses of

the clay model are: (1) a lack of environmental set-

tings that support clay evolution and stability; (2)

the late development of cellularization; and (3) the

inability of the model to explain the relation

between microorganisms and the presumed traits

of early life.

Pyrite-based template. While the clay-model,

like the Oparin-Haldane model, assumes that the

organic molecules necessary for cell formation and

polymerization were provided by a thin soup in

the surroundings of the clay crystals, the pyrite-

based template model rejects this concept and pos-

tulates the inorganic origin of life instead. In this

scenario, organic molecules were synthesized in

high temperature environments comparable to hy-

drothermal vents on the surface of growing pyrite

crystals, which form from the reaction between fer-

rous sulfide and hydrogen sulfide. During the proc-

ess of pyrite formation, electrons are released,

which, due to the catalytic properties of the pyrite

crystal, can be transferred directly to carbon diox-

ide. (In a later version of the theory based on ex-

perimental results, carbon monoxide replaced car-

bon dioxide.) In this process, simple reduced

compounds like formic and acetic acid were

formed. In addition to their catalytic properties, the

positive charge of pyrite crystals allows them to re-

tain the newly-synthesized negatively-charged or-

ganic molecules. Consequently, organic molecules

accumulated on the pyrite surface, steadily coating

it with an organic layer in a process of cellulariza-

tion. It can thus also be attributed a selective prop-

erty of the surface charge of the pyrite crystal: Mol-

ecules that do not stick to the crystal are lost by

diffusion and do not participate in further

processes. As simple molecules polymerized on

the surface of the pyrite crystal, gradually more

complex molecules were formed, including a

membrane-like layer, which enclosed the pyrite

crystal. In the pyrite model, metabolism came first.

For a long time, competing cell-like structures re-

sulted exclusively from the structuring properties

of the pyrite crystal, which both served as the en-

ergy and electron source for carbon fixation, and as

a cellularization nucleus without the involvement

of information carriers such as RNA and DNA.

Unlike the other models, it is a major concern

of the proponents of the pyrite model that all spe-

cific predictions, at least in principle, stand up to

experimental investigation. Hitherto, several pre-

dictions deduced from the pyrite model have been

verified experimentally. In addition, the presence

of iron sulfur clusters in the catalytic centers of an-

cient enzymes has been interpreted as the remains

of a pyrite past. Still the model is not without prob-

lems. Most of the criticism concerns the environ-

mental sites where pyrite life potentially could have

occurred. Hydrothermal vents are relatively short-

lived structures, which limits the time available to

pyrite-based life formation at a particular site. In

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addition, the high temperature, which may be re-

quired for some types of synthesis, may effect other

processes negatively. Another serious concern ad-

dresses the phosphate necessary for the initial sur-

face binding of organic compounds to pyrite. Be-

cause of precipitation, typical vent environments

are strongly depleted in phosphate. If the same

holds true for ancient vent systems, it is difficult to

explain how life could have originated there.

RNA-world model. The most popular scenario

of the origin of life is the so-called RNA-world

model, which elaborates on the Haldane-Oparin

theory. The RNA-world model proposes that RNA

molecules were the precursors of proteins as cata-

lysts and of DNA as information carriers. This con-

cept gained support when the catalytic properties

of modern RNA molecules were demonstrated.

Proponents of this theory introduced the term ri-

bozyme, which stresses the functional similarity of

RNA molecules to protein molecules, in addition to

their already established role as informational mol-

ecules. The following scenario has been outlined

for the development of the RNA world: (1) Short

RNA molecules formed from random combination

of mononucleotides; (2) Some oligonucleotide

structurally include the potential of catalyzing the

synthesis of complementary copies of themselves,

with the chemical energy for the process provided

by reactive molecules combined with the mononu-

cleotides; (3) RNA molecules developed that cat-

alyzed their own synthesis, and as a consequence

evolution by natural selection became possible.

Stage three in the RNA-world scenario can be

summarized by the so-called hypercycle model,

which links related RNA molecules in the form of

a catalytic cycle. The interaction between RNA

molecules was already characterized by a selec-

tion-constrained evolution potential. Steps one and

two of the RNA-world model have some short-

comings which have yet to be overcome. These

shortcomings include the synthesis of important

components of the RNA molecule such as sugar ri-

bose and reactive phosphate molecules. It has

been proposed that not RNA itself but a simpler

RNA-like molecule was at the origin of life.

Self-organizing models

As an alternative to the template-based scenarios

described above, scientists have developed a theo-

retical framework that is based on the concept of

catalytic closure. Here life started as autocatalytic

sets of molecules, which means that all the mole-

cules within the set catalyze their formation, and

also catalyze the formation of their catalysts. A hy-

percycle is based on the interaction between RNA

molecules. In principle, protein-based cycles or cy-

cles which combine different types of macromole-

cules may also exist.

The scientific theories of the origin of life pre-

sented here are only preliminary and require nu-

merous experiments and sophisticate modeling be-

fore they can gain general acceptance. At best,

researchers will find answers to most of the open

questions. At worst, they will end up producing

more questions than they answer. The conse-

quences of such scientific concepts for philosoph-

ical and religious traditions are likely to be mar-

ginal as the latter address mainly phenotypical

expressions of living processes rather than “hap-

penings” in the distant past.

See also AUTOPOEISIS; BIOLOGY; EMERGENCE;

VOLUTION, BIOLOGICAL; LIFE, RELIGIOUS AND

PHILOSOPHICAL ASPECTS; LIFE SCIENCES

Bibliography

Brack, Andre, ed. The Molecular Origins of Life, Assem-

bling Pieces of the Puzzle. Cambridge, UK: Cambridge

University Press, 1998.

Crains-Smith, A. G. Genetic Takeover and the Mineral Ori-

gins of Life. New York: Cambridge University Press,

1982.

Davies, Paul. The Fifth Miracle: The Search for the Origin

and Meaning of Life. London: Penguin Books, 1995.

Dyson, Freeman. Origins of Life. Cambridge, UK: Cam-

bridge University Press, 1999.

Eigen, Manfred, and Peter, Schuster. The Hypercycle: A

Principle of Natural Self-Organization. New York:

Springer, 1979.

Kauffman, Stuart. Investigations. Oxford: Oxford Univer-

sity Press, 2000.

Oparin, Aleksandr. The Origin of Life on the Earth, 3rd

edition, trans. Ann Synge. Edinburgh, UK: Oliver and

Boyd, 1957.

Schrödinger, Erwin. What is Life: The Physical Aspect of

the Living Cell. Cambridge, UK: Cambridge University

Press, 1944.

Wächtershäuser, G. “Groundworks for an Evolutionary

Biochemistry: The Iron-Sulfur World.” Progress in

Biophysics and Molecular Biology 58 (1992): 85–201.

KAI FINSTER

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LIFE,RELIGIOUS AND

PHILOSOPHICAL ASPECTS

Life is literally a biological term but extends by

metaphor across a spectrum of key concerns in phi-

losophy and religion. Life is a perennial experience,

prescientific and universal in cultures ancient and

contemporary, though recent advances in the bio-

logical sciences have recast classical ideas about life

in new perspectives. By some accounts, molecular

biologists decoding the human genome have dis-

covered the “secret of life”; by other accounts evo-

lutionary biologists have discovered the “secret of

life” in natural selection. Philosophers, ethicists, and

theologians reply with claims that, though science

may teach much descriptively about life, it cannot

teach how to value life and what one ought to do.

From the dawn of religious impulses, in the

only animal capable of such reflection, this vitality

has been experienced as sacred. Such experience

has often been fragmentary and confused, as has

every other form of knowledge that humans have

struggled to gain, but at its core the insight devel-

oped that religion was about an abundant life,

about life in its abundance. Classical monotheism—

to take the Hebrew form of it—held that the divine

Spirit or Wind (Greek: pneuma) breathes the breath

of life into the dust of the earth and animates it to

generate swarms of living beings (Genesis 2:7).

Eastern religious forms can be significantly differ-

ent: Maya spun over Brahman, or samsara over

sunyata; but they too detect the sacred in, with,

and under the profuse phenomena of life.

If anything is sacred, life is sacred. For theists,

life, above all, is a gift from God. Elemental necessi-

ties, such as bread, water, blood, breath (pneuma),

and birth are often taken up as symbols in religions.

Native traditions may regard Earth, soil, waters,

everything as alive. Scientists may now dismiss this

as an innate tendency to be animistic, to ascribe liv-

ing properties to inanimate forces. But quite sophis-

ticated philosophical systems, such as panpsychism,

pantheism, and forms of idealism, have held that ul-

timate reality is organic or spirit-like.

Organic life

Philosophical and religious concerns about life can

be broadly divided into those involving life gener-

ically and those focusing on human life. One in-

tense debate arising in the last half century has

been over intrinsic value in life, whether organisms

have value in themselves, and not simply instru-

mental value for humans. The background to this

debate is an Enlightenment tradition of a value-

free nature, seemingly plausible in the inanimate

world of stars, asteroids, rocks, or dirt, an account

continued by many biologists in a mechanistic bi-

ology, which views organisms as nothing but ma-

chines. However, contemporary biologists have

not only described but come to celebrate the di-

verse array of forms of life (species, families,

phyla), to systematize these, and then lament that

humans are placing so many of them in jeopardy.

Conservation biology today is as dominant and re-

markable as is molecular or evolutionary biology.

The panorama of life on Earth, biologically de-

scribed, raises issues of whether the species can

also be ranked or graded for their worth. Levels of

life move from microbes to multicellular plant and

animals, with “higher” animals sentient, many of

them capable of acquired learning during their life-

times, and the “higher” of these enjoying psycho-

logical experiences, the “highest” of all human life

with self-conscious experience, capable of gener-

ating meaningful communities gathering into cu-

mulative transmissible cultures. Other thinkers,

claiming a more egalitarian and less biased ac-

count, object to such hierarchy and anthropocen-

trism, advocating a biocentrism where all are val-

ued with respect to their multiple and differing

achievements and skills, including humans, but not

preferential to humans. The capacity for photo-

synthesis is as valuable on Earth as is the capacity

for ethics.

Darwinian natural history reveals an ambiguity

in life, often taken to be problematic. Life is a cease-

less struggle; new life is generated by blasting the

old. Darwinians may focus on the survival of the

fittest, accentuating the competition in life, famously

described by the nineteenth century English poet

Alfred Lord Tennyson as “Nature, red in tooth and

claw.” Charles Darwin as well portrays connected-

ness in life, common ancestry, survival of the best

adapted, life support in ecosystems, life persisting

in the midst of its perpetual perishing, life generated

and regenerated in spectacular biodiversity and

complexity, with exuberance displayed over 3.5 bil-

lion years, an “abundance of life.” Such a view of

life echoes ancient religious motifs: Life is a table

prepared in the midst of enemies, green pastures in

the valley of the shadow of death.

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Debate continues over whether the natural his-

tory of life on Earth is orderly, probable, inevitable,

or contingent; over what mixture of law and open-

ness characterizes it; and whether biological

processes are adequate to account for life’s origin

and evolving diversity and complexity. Molecular

biologists have discovered hitherto unsuspected in-

tricacy and complexity at the molecular level, also

endorsing life with its unity in diversity, and leav-

ing as intense as ever the religious concerns about

what to make of life, and what abundant life is

possible and appropriate for humans.

The distinctiveness of human life

Turning to human life, a recurrent issue is whether

and how human life is distinctive. The biological

sciences evidently supply connections; humans

differ in their protein molecules from chimpanzees

by only a fraction of a percent. But the startling

successes of humans doing biological sciences

can as readily prove human distinctiveness:

Chimpanzees have no capacities for cumulative

transmissible cultures leading to a science by

which they can decode their own genes, much less

can they debate the ethics of cloning or have their

religious convictions challenged by reading Dar-

win’s Origin of Species.

Various human activities have their parallels

and precursors in animal behaviors; animals get

sleepy, angry, suffer pains, enjoy pleasures.

Equally, myriads of human capacities are sui

generis; animals do not pray, or seek forgiveness

for sin, or worry whether the theory of relativity

relativizes ethics. Humans are persons, made (as

theologians like to say) “in the image of God.”

They have Existenz (as the Existentialists say). Hu-

mans anticipate death; they sense their finitude;

they face limit questions. They know guilt, for-

giveness, shame, remorse, glory, pride. They suffer

angst and alienation. They build symbols with

which they interpret their place and role in their

world. They create ideologies, affirm creeds, and

debate their rights and responsibilities. They are

capable of religious faith and the worship of God.

Many of them sense the sacred, worry about com-

munion with the ultimate, or atonement of their

sins. All of this can be summed up in the one

word: spirit. In this life of the spirit, humans, late-

coming on the planet, remain remarkably distinc-

tive from the other millions of species, indeed the

billions that have come and gone over evolution-

ary time.

One distinctive characteristic of human life is

its brokenness, and here the religions classically

offer salvation, or the good life. “I have set before

you life and death, blessing and curse; therefore

choose life” (Deuteronomy 30:19). Jesus says “I am

the way, the truth, and the life” ( John 14:6). The

metaphor may be of new life; one is born again, or

regenerated. This re-forming of life appears to

many philosophers, ethicists, and theologians to

be the area in which biology has so little pur-

chase—the “ought to be”—however much biology

has decoded what is describing the metabolisms

and evolution of life, or perhaps found so-called

selfish genes that dispose our behavior.

The relevance of religion to scientific

explanations

Humanists may resist claims that biology explains

religion, finding the secret of life in genes or in nat-

ural section, or finding that religion is (nothing

but) a mythical belief system that favors survival.

Theologians turn the tables, arguing that religion is

needed to explain biology, that the prolific genesis

of life on Earth, documented in natural history,

generates religious responses. The prolific earthen

fertility, or generative capacity, in which humans

find themselves immersed, is what most needs to

be explained. Humans alone confront the ethical

duty of appropriate respect for such life, including

their own human life. Nothing in biology settles

questions about the meaning of life.

Advances in our biological understanding of

life, as well as medical and technological capacities

to intervene, have raised new issues that involve

the beginning and ending of life (such as cloning,

abortion, and euthanasia). Other advances make

life more of a commodity (as with farm agriculture,

genetically modified crops, stem cell lines, or

patented genes).

Ethicists frequently claim that our concern

ought to be for quality of life, not just life—and

again religious convictions can seem as relevant as

biological facts. Biology can set some standards for

whether organisms are flourishing or diseased;

quasi-evaluative terms such as “health” or “in-

tegrity” do have a foundation in biology. Beyond

that, the quality of life demands evaluative judg-

ments about right and wrong, censure and blame,

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good and evil. Life requires choosing a lifestyle.

Life demands respect, and this respect passes over,

often imperceptibly, to reverence. Though a secu-

lar science, biology invites an inquiry into the sa-

cred.

Life has death as its opposite, or complement.

Life survives death on Earth by reproducing bio-

logically. Religions ask about the quality of life on

Earth, but the inevitable earthen death of individu-

als raises the question of life after death, of eternal

life, of what survives the bodily demise of an indi-

vidual. Religions answer this question variously.

Some, especially Eastern religions, suppose rebirth

and reincarnation, a sequence of lives on Earth or

in other worlds. Western monotheism, in Islam and

Christianity, has favored life on Earth consum-

mated in life in heaven, perhaps by a continuing

immortal soul, or spirit, outliving the body, per-

haps by a resurrection of the body. A perennial

faith expects continued life in the spirit gathered

into the Divine Spirit.

See also LIFE, BIOLOGICAL ASPECTS; LIFE SCIENCES

Bibliography

Barbour, Ian G. Religion and Science: Historical and

Contemporary Issues. San Francisco: Harper,

1997.

Birch, Charles, and Cobb, John B. Jr. The Liberation of

Life: From the Cell to the Community. Cambridge, UK:

Cambridge University Press.

Darwin, Charles. The Origin of Species (1859). New York:

Bantam Classic, 1999.

Hefner, Philip. The Human Factor: Evolution, Culture, and

Religion. Minneapolis, Minn.: Fortress Press, 1985,

McCormick, Richard A. “The Quality of Life, the Sanctity

of Life.” Hastings Center Report 8, no. 1 (1978): 20–36.

Pannenberg, Wolfhart. Anthropology in Theological Per-

spective. Philadelphia, Pa.: Westminster Press, 1985.

Peacocke, Arthur R. Creation and the World of Science.

Oxford: Clarendon Press, 1979.

Rolston, Holmes, III. Genes, Genesis and God: Values and

their Origins in Natural and Human History. New

York: Cambridge University Press, 1999.

Russell, Robert John; Stoeger, William R.; and Ayala, Fran-

cisco J. eds. Evolutionary and Molecular Biology: Sci-

entific Perspectives on Divine Action. Vatican City:

Vatican Observatory Publications, 1998.

Sterelny, Kim, and Griffiths, Paul E. Sex and Death: An

Introduction to Philosophy of Biology. Chicago:

University of Chicago Press, 1991.

HOLMES ROLSTON, III

LIFE SCIENCES

The life sciences, defined as biology and related

subjects, encompass the detailed study of living or-

ganisms, which are broadly distinguished from in-

organic matter through the capacity for growth,

function, and change preceding death. Biology is

not limited to physiology, the study of the growth

and function of living organisms. It also includes

the study of biochemical reactions taking place in

particular cells of particular organs. At a physical

level, biophysics considers, for example, electrical

changes taking place across membranes. Even

more specific is the field of molecular biology,

which attempts to unravel the changes that occur

in molecules during biochemical reactions. Genetic

science is the study of molecules that act as tem-

plates of information for certain biochemical reac-

tions and that are passed on to the next genera-

tion. Yet the life sciences include the study of more

than just the interior of living organisms and the bi-

ological reactions in the cells of living organisms.

The life sciences also include ecology, the study of

the exterior context of particular environments and

the interrelationships between species. More

broadly, animal behaviorists examine the way ani-

mals react to environments, and psychologists ex-

plore the possible reasons for this behavior.

The different life sciences pose challenges to

theological and religious interpretations of reality.

Put simply, if the life sciences can offer explana-

tions for the way life functions on Earth, there is no

need to invoke a divine creator. Is it possible to re-

cover the belief held in the seventeenth century

that all aspects of creation are the works of a di-

vine mind? Or, if one accepts that God creates the

world through the processes of biology, how far

might it be possible to take such knowledge into

human hands? Do people have the right to become

co-creators with God in shaping the course of their

own evolution and that of other species? One’s

view of ethics will depend on the particular view

of God that one presupposes. Another question

often asked is how far the scientific understanding

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of life is equipped to answer the complex ethical

questions that have emerged in contested areas

such as genetics and environmentalism. In these

scenarios it may be that theology has more to offer

than simply a response to the problems that sci-

ence poses to its own fundamental beliefs.

Exploring the science

Having given a rough sketch of the range of sci-

ences included in the concept of the life sciences,

it is necessary to explore the task and presupposi-

tions of the different sciences in order to under-

stand their theoretical interrelationships. Molecular

biology, for example, made a dramatic contribu-

tion to the study of genetics by defining the double

helical structure of deoxyribonucleic acid (DNA)

found in chromosomes. This discovery, published

in 1953, is attributed to James Watson and Francis

Crick, although Rosalind Franklin and Maurice

Wilkins also provided vital experimental data. DNA

consists of two strands of sugars and phosphates

that are joined together by pairing of particular

bases attached to the sugars. The pairing of bases

is always the same, adenine with thymine and cy-

tosine with guanine. The DNA unravels once a

gene becomes active so that a particular section of

DNA codes for a particular carrier nucleic acid, and

thence to a particular protein. Moreover, the DNA

can replicate itself by unwinding, after which each

single strand pairs with another.

Once scientists defined the structure of DNA, it

became possible not only to understand the rea-

sons for genetic diseases, but also to develop ways

of changing DNA structure by cutting or adding

particular sections of DNA to the existing template.

The practical science to which genetics relates

most naturally is medicine, though it also has im-

plications for commercial use in biotechnology.

It is possible to think about the sciences as op-

erative at different levels in the study of living or-

ganisms. At the most fundamental level, molecular

biologists examine changes in molecules during

particular reactions. However, some would argue

that the physical changes taking place are even

more primary than this, so that changes in physical

fields are coincident with certain chemical and mo-

lecular changes. The movement of charged mole-

cules or ions across membranes, for example, is

accompanied by electrical changes in the mem-

brane. Biophysicists are interested in unravelling

the details of such changes. At the next highest

level, cell biologists explore reactions taking place

at a cellular level, for example, the biochemical in-

terchange between different parts of the cell or or-

ganelles. Cells make up organs, and the decipher-

ing of the function of different organs in relation to

the overall health of the organism delineates the

field of physiology. For example, the way organ-

isms use nutrients is the concern of physiologists.

The idea of nutrients is suggestive of the interac-

tion between the organisms and their environment,

and one of the concerns of ecologists is nutrient

exchange between species.

Ecology is important as far as the human sci-

ences are concerned because it bears on human

interrelationships with other living creatures. At

the broadest level, geophysiologists examine the

relationship between living creatures and the

planet as a whole. This science, provocatively

named the Gaia Hypothesis by James Lovelock in

1969, suggests a different way of doing science,

one that, like ecology, examines relationships,

rather than biochemical or biophysical reactions.

Lovelock’s hypothesis is that the Earth’s relatively

stable temperature and the gaseous composition of

its atmosphere are not accidental; rather the sum

total of all living things, or biota, directly con-

tribute to this stability. His hypothesis is difficult to

prove, so it has been marginalized by the scientific

establishment.

The history of the way life emerged on the

planet looks to fundamental questions about the

origins of life itself. Charles Darwin’s theory of evo-

lution explored the biological processes that un-

derlie the diversity of life on this planet. His theory

of natural selection states that the survival of indi-

viduals in a species depends on those characteris-

tics that render them most fit for a particular envi-

ronment, and therefore most able to have the most

offspring. The scientific study of genetics has de-

fined more precisely the mechanism through

which these characteristics are inherited. Evolu-

tionary ideas link genetic science with ecological

science. On the one hand, the history of the evo-

lution of species depends on genes passing from

one generation to the next, the so-called selfish

gene theory exemplified most famously by biolo-

gist Richard Dawkins. On the other hand, the ways

genes are expressed depend on a particular envi-

ronment, so that the combined effect of genetics

and environment makes up the phenotype of the

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individual organism. Lovelock’s hypothesis chal-

lenges the assumption that organisms are always

adapted to their environment by suggesting that

the activities of organisms in and of themselves not

only influence but also regulate their environment.

Most biologists, however, accept Darwin’s basic

theory of natural selection.

The life sciences are not only concerned with

the history or origin of life on Earth—they also

have their own story of development. Ecology, for

example, in the early part of the twentieth century

considered its task to be the examination of suc-

cession of plant communities that established par-

ticular habitats, niches, or homes for other species.

After 1945 ecologists began to look at the relation-

ships between species in terms of energy ex-

change, all contributing to a particular ecosystem.

Ecosystems lend stability and equilibrium to com-

munities of organisms, however, ecologists have

become less convinced that ecosystems function as

stable communities. Instead of balance there is dis-

turbance; instead of equilibrium, there is a fluid

landscape of different, loosely assembled, environ-

ments. In addition, the scale of measurements used

is important; ecology could be studied at the level

of the leaf, canopy, patch, or forest, moving up the

scale of organization. Higher up the scale different

emerging properties appear. Debates exist con-

cerning the degree to which these properties are

simply dependent on activities at the lower levels

of organization (bottom-up causation), are unique

to their own level, or perhaps even a result of ac-

tivities further up the scale (top-down causation).

Emergent properties are still open to scientific con-

sideration. The philosophical idea that these prop-

erties consist of the addition of a unique substance

known as vitalism is rejected by contemporary sci-

ence. Some writers, by their suggestion that Gaia is

a living organism, have interpreted Lovelock’s

ideas in such a way that it comes close to this

view.

Exploring issues in science and religion.

Darwin’s theory of evolution poses challenges to

the Christian idea of divine creation and design.

The way theologians respond to this challenge is

likely to influence the way they approach the life

sciences in general. For example, if Darwin’s the-

ory is rejected, then it is likely that a conservative

approach to genetic science will ensue, and there

will be resistance to most, if not all, genetic engi-

neering. According to this view, the diversity of

species on the planet is the result of divine fiat as-

sociated with the story of Genesis.

Those in broad agreement with Darwinian sci-

ence may either retain a classical model of God as

creator of the world, with God creating through

evolutionary processes, or they embed their view of

God more specifically in biological processes them-

selves, so that God evolves with biological change.

While both views can support technological

change, the emphasis is different. For Celia Deane-

Drummond, for example, God may be viewed as

divine wisdom, which creates the world in love

through wisdom. Hence the diversity of life is af-

firmed as the gift of God. Each species needs to be

given respect on the basis that each is loved by

God, even though God has allowed changes to

evolve. Although the classical view of God is asso-

ciated with an understanding of God as omnipotent

and omnipresent, it is possible to affirm the tran-

scendence of God without assuming a static and re-

mote model of who God is. If changes are to be

made in the genetic makeup of species, then these

changes need to take into account the particular

telos or purpose of each individual species as far as

it is possible to understand it. Moreover, those who

do attempt to re-order the natural world via bio-

chemistry need to be aware that it requires a par-

ticular gift, namely the gift of wisdom and discern-

ment, in order to assess the limits of such attempts.

The alternative view perceives God not so

much as “other” to creation, but as one who allows

creation to emerge and become itself through di-

vine activity. Accordingly, for Philip Hefner, humans

can become co-creators with God and look to their

individual freedom and individuality as the basis for

change. Just because humans have more freedom

does not mean that God is in some way restricted in

freedom. Genetic determinism is rejected by many

authors, such as Ted Peters, who argue that human

beings are more that just products of genetic activ-

ity. As co-creators humans have the authority to

make changes to the genetics of human and other

species. The suffering of those with genetic diseases

engenders compassion that calls for action. The fail-

ure to contribute to such a change when the knowl-

edge exists amounts to apathy, rather than arro-

gance. There are important issues in human

genetics, but the issues depend more on analysis of

the risks and benefits of particular actions, rather

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