Analysis and argument for scientific naturalism. Subject: God and the Natural Sciences, 2018 Semester 1 University of Melbourne

1. Scientific Naturalism
God and the Natural Sciences
2018
John Wilkins

2. Dealing with natural explanations
It is common to hear religious claims that science is just an
ideology
Science, it is said (Phillip Johnson) has its belief and high priests
Hence, when religious and scientific claims conflict, this is a
conflict of wordviews not facts
Bishop Butler wrote in a sermon in 1729:
“ Things and actions are what they are, and the consequences of
them will be what they will be: why, then, should we desire to be
deceived? [Sermon 7]
Why indeed?

3. Varieties of “Naturalism”
Many meanings
▫ The view that all that is, is natural
▫ The view that natural explanations are the
only legitimate kinds of explanations
▫ A philosophical project in which things that
are previously thought to be inexplicable by
science are shown to be explicable by science
 Mind and consciousness
 Meaning of language
 Ethics and morality

4. What is “nature”
It seems we must be circular:
▫ Nature is what natural science studies
▫ Natural science is what our studies of nature result in
▫ So, what is “nature” for our purposes?
John Stuart Mill (1806–1873) gave a definition:
▫ what is meant by the “nature” of a particular object
…? … the ensemble or aggregate of its powers or
properties: the modes in which it acts on other
things (counting among those things the senses of
the observer), and the modes in which other things
act upon it

5. What is “nature”?
“As the nature of any given thing is the
aggregate of its powers and properties, so
Nature in the abstract is the aggregate of the
powers and properties of all things. Nature
means the sum of all phenomena, together
with the causes which produce them;
including not only all that happens, but all that is
capable of happening; the unused capabilities of
causes being as much a part of the idea of
Nature as those which take effect.”
John Stuart Mill, “On Nature”, Nature: the utility of
religion and theism (1874)

6. Regularities of nature
Something may be thought to be “natural”
if:
• It is consistent in its behavior (lawlike)
• Evidence is available to all observers
(empirical)
• It does not depend upon the nonempirical
beliefs of observers and explainers
• It explains the phenomena (theory-like)

7. The nature of Naturalism
Naturalism goes back to the early Hellenic philosophers
(the “Ionian Enlightenment”), who held that things behave
as they do due to their inherent natures
In the 19thC, “scientific naturalism” arose to try to explain
everything in terms of natures.
▫ Excluded supernatural interventions (whims of the gods)
▫ Tried to establish values as human nature (cf. Daoism)
and the good life as the natural one
▫ Tried to explain consciousness and experience as natural
processes

8. The argument is simply this. The spatio-temporal
system certainly exists. Whether anything else exists
is controversial. If any entities outside the system
are postulated, but have no effect on the system,
there is no compelling reason to postulate them.
Occam’s razor then enjoins us not to postulate them.
David M. Armstrong. 1978. “Naturalism, materialism and
first philosophy”, Philosophia, 8 [2-3] 261–276

9. Three varieties of naturalism
“I distinguish methodological naturalism, meaning that in doing
science one assumes that there are no God-directed supernatural
causes like miracles, and metaphysical naturalism which is
equivalent to atheism, meaning that there are no supernatural factors
or entities, full stop.”
 Michael Ruse, “Atheism, naturalism and science: three in one?”
I prefer:
1. Normative naturalism: values and ethics
2. Ontic naturalism: realism and object
3. Methodological naturalism: knowledge and method
And I do not like to define these in terms of the supernatural (for
reasons below)

10. Normative (moral) naturalism
“the object of the present Essay… is … to
inquire into the truth of the doctrines which
make Nature a test of right and wrong, good and
evil, or which in any mode or degree attach
merit or approval to following, imitating, or
obeying Nature.”
 Mill, “On Nature”
Led to evolutionary accounts of morality
Criticized by G. E. Moore as “the naturalistic
fallacy”

11. The Naturalistic Fallacy
“… ethical theories which declare that no intrinsic value is to be
found except in the possession of some one natural property,
other than pleasure; and which declare this because it is
supposed that to be good means to possess the property in
question. Such theories I call Naturalistic.” §23
“… far too many philosophers have thought that when they
named those other properties they were actually defining
good; that these properties, in fact, were simply not other, but
absolutely and entirely the same with goodness. This view I
propose to call the naturalistic fallacy…” §10
 G. E. Moore, Principia Ethica (1903) [emphases added]

12. Ontic naturalism
Originally called materialism
▫ The doctrine that all that exists is matter
Now referred to as physicalism
▫ The doctrine that all that exists is physical
An ontological claim: about what exists
▫ Only that which the best science says exists
Often connected to reductionism
▫ The doctrine that mind and other such
phenomena can be reduced to a physical state

13. Reductionism is a good thing
You will hear people saying “That’s
very reductive” as a criticism
In science, reducing one theoretical
description to another theoretical
level is a good thing.
It means we need one fewer theory
to explain the natural world
Criticism of reductionism relies on
question-begging about what
exists
▫ E.g., life, mind, social facts
This is an epistemic issue

14. Methodological naturalism
The doctrine that our knowledge is purely natural
• Applies to philosophical method
• In religious debates, applies to scientific
knowledge
Has an issue with methodological rules and norms
• Are norms natural? (subject to the naturalistic
fallacy?)
• If not, then method is not naturalistic
Some hold that method and knowledge are relative
to worldviews

15. Wordviews
In German: Weltanschauungen or Weltansicht
Supposedly a coherent set of beliefs about the
world:
▫ That determine our interpretation of
experience
▫ That determine our explanations of
phenomena
▫ That determine what is true (in that Worldview)
 “What is true for you is not true for me”

16. I do not believe in Worldviews
Nobody is born with a Worldview
▫ Therefore we acquire it over time
▫ However, we acquire our beliefs piecemeal
▫ So it is very unlikely we have a coherent set of
beliefs
Do societies have Worldviews?
▫ There are leading beliefs in societies
▫ However, they are also conflicting and piecemeal
▫ Even in religious institutions and movements

17. Naturalism is not a Worldview
If there are no worldviews, what is
naturalism?
▫ It is a method for uncovering the natures of
things
▫ It is a presumption (not a presupposition)
that nothing should be given a non-natural
explanation
▫ Hume’s argument applies here:

18. Hume, On miracles
“A miracle is a violation of the laws of nature; and as a
firm and unalterable experience has established these laws,
the proof against a miracle, from the very nature of the fact, is
as entire as any argument from experience can possibly be
imagined.” §10.12
“… no testimony for any kind of miracle has ever amounted to
a probability, much less to a proof; and that, even supposing it
amounted to a proof, it would be opposed by another proof;
derived from the very nature of the fact, which it would
endeavour to establish. It is experience only, which gives
authority to human testimony; and it is the same experience,
which assures us of the laws of nature.” §10.35
 An Enquiry concerning Human Understanding (1748) [emphases added]

19. In short
We have a broad reason to accept the
natural order – laws, observations,
experiments – and, weighing that against
evidence for the non-natural, little reason to
accept the non-natural
▫ We have natural explanations for “non-
natural” experiences
▫ The “supernatural” is defined against the
natural order

20. Mind
The functioning of the mind is, I think, the
functioning of an embodied social brain
“Consciousness” and “experience” is either
1. An artefact of our ordinary language (like “I”
or “feel”; or
2. A property of being a particular body over
time in a particular space; or
3. The practices and expectations of our social
context;
Or all three…

21. Morality [norms]
We are apes – social hierarchical animals – so
we have norms and rules
We have symbolic language, so we express
these as ought-statements
Ethical language is a process of justification for
these statements
Cultural evolution leads to the values that
underlie ought-statements
Morality is culturally relative and only partly
based on evolved properties of humans

22. Implications of naturalism
Creationists and Intelligent Designists hold that
naturalism (esp. science) is just another worldview
Some theologians think that naturalism is prejudiced
against a deity’s existence (i.e., is question-begging)
Some argue that it is self-defeating (Alvin Plantinga’s
Evolutionary Argument Against Naturalism – EAAN)
Scientism: the over-reach of science?
▫ Is it defineable?
▫ Does naturalism require it?

23. Evolutionary debunking arguments
• It has been argued that if morality evolved,
then we can have no confidence morality is
objective, as selection maximizes fitness not
truth
• Plantinga argues this is true of science:
naturalism is not reliable because it is selected
for fitness (tiger example)
• Paul Griffiths and I argue science is fit because
it leads to truth (as also is commonsense)

24. The tiger in the grass
Plantinga:
• We might flee from a tiger because we think it likes to play
• Increases fitness via untruth
Wilkins and Griffiths:
• Might work in one case
• Very unlikely to work
over all cases
• Some fitnesses track
truth; others do not

25. What about spirituality?
A lot of folk refer to being “spiritual”
▫ Consider Wordsworth:
 Sweet is the lore which Nature brings;
Our meddling intellect
Mis-shapes the beauteous forms of things:--
We murder to dissect. [“The tables turned”, 1798]
Naturalism does not reject the wonder of
nature
▫ It explains it: Wilson’s “biophilia” for
example

26. Does a naturalist have to be an atheist?
If you adopt normative naturalism, maybe
(unless your deity doesn’t prescribe absolute
values)
If you adopt ontic naturalism, maybe (if
your deity is physical or natural)
If you adopt methodological naturalism, no

27. Readings and references
Johnson, P. E. (1995). Reason in the balance: the case
against naturalism in science, law & education.
Downers Grove, Ill., InterVarsity Press.
Butler, J. (1726). Fifteen Sermons preached at the Rolls
Chapel, etc, pp. 312. J. & J. Knapton: London.
Mill, J. S. (1874). Nature: the utility of religion and
theism. London, Longmans Green Reader and Dyer.
Armstrong, D. M. (1978). “Naturalism, materialism and
first philosophy”, Philosophia, 8 [2-3] 261–276.
Moore, G. E. (1903). Principia Ethica. Cambridge UK,
Cambridge University Press.
Hume, D. (1894). An Enquiry concerning the Human
Understanding, and an Enquiry concerning the
Principles of Morals ... Reprinted from the ... edition of
1777, and edited, with an introduction ... by L. A.
Selby-Bigge. Oxford, Clarendon Press.
Papineau, D. (2010). “Naturalism”, Stanford
Encyclopedia of Philosophy. [link]
Plantinga, A. (2002). The Evolutionary Argument
against Naturalism. Naturalism Defeated? Essays on
Plantinga's Evolutionary Argument against Naturalism.
J. K. Beilby. Ithaca, NY, Cornell University Press: 1–
13.
Wilkins, J. S. and P. E. Griffiths (2013). Evolutionary
debunking arguments in three domains: Fact, value,
and religion. A New Science of Religion. J. Maclaurin
and G. Dawes. Chicago, University of Chicago Press:
133–146.
Also: Griffiths, P. E. and J. S. Wilkins (2014). When do
evolutionary explanations of belief debunk belief?
Darwin in the 21st Century: Nature, Humanity, and
God. P. Sloan. Notre Dame, IN, Notre Dame University
Press.