1 Defining design
Designing and making
5 Irreducible complexity
6 Intelligent design
7 Probability: fine-tuning
9 Claims and evidence
10 Theistic arguments from design
A so-called argument from design claims that a design is evidence for the existence of a designer. So the first question is: what is a design?
In the phrase argument from design, the word design is an abstract noun, because ‘design’ is not a real thing. There are real things, such as drawings or plans, that
we may call designs. But apart from those, there is no real thing that is ‘design’.
(To say ‘design’ is an abstract thing or object, or a concept, is to
mistake a word such as design for a thing of some kind that we can at least try to describe. Metaphysicians have been making this mistake with abstract nouns for millennia.)
reality, to define ‘design’, all we have to go on is the way we use the word design in different contexts. For example, a building has a design, and the architect or builder is its designer. In this case, an argument from design to a designer
is usually sound, for two reasons.
First, in our experience, buildings do not design and build themselves. And second, there is often a trail of evidence leading back from the building
to its designer. (And if there is no such evidence – in our experience, buildings do not design and build themselves.)
2 Designing and making
The expression argument from design can be misleading, because, usually, the evidence offered to support the argument is not a real design, such as a drawing or plan. Instead, the evidence offered is
a real thing with what is claimed to be a designed structure or function. Such an argument is really an argument from a designed thing.
So, in practice, an argument from design
is usually an argument from a putatively made thing to the existence of a maker who had to design that thing, or at least work from a design, in order to make it.
Some arguments from design conflate structure and design, blurring the distinction. All natural things have a structure. And the natural sciences try to describe those structures and explain how
they appear and change by physical processes.
In some contexts, we do use the words structure and design as synonyms, without confusing consequences. But in arguments
from design, the assumption that structure is the same thing as design may lead to mistakes.
A structure may be the product of design by a designer. But that must be demonstrable in each
case. Structure and design are not the same thing.
Some arguments from design claim
that the complexity of a thing’s structure or function is evidence that it was designed. The assumption is that un-designed things tend to be simple, such as a naturally occurring rock.
like the word design, the word complexity is an abstract noun, because ‘complexity’ is not a real thing. And in practice, whether we call a thing simple or complex depends on the kind of description we are producing.
For example, the chemical or atomic structure of a naturally occurring rock could be extremely complex.
So, as with design itself, complexity may be evidence for a designer. But the claim
that what we call a complex thing had, or is likely to have had, a designer must be demonstrable in each case.
Another problem with an argument from complexity is that a feature of good
design is often not complexity, but rather simplicity, which can mean efficiency and economy. So the argument that complexity is always evidence for a designer is unsound.
Some arguments from design claim that a thing is not only complex, but also irreducibly so. This means its structure or function cannot have come, or is unlikely
to have come, from natural processes combining simpler things. Candidates for irreducible complexity have included the mammalian eye, the human brain, cell structure and DNA.
But the modifier
irreducible implies a contrast with reducible complexity. Unless we know what reducible complexity is – and how it differs from irreducible complexity – the nature of irreducible complexity is unclear. The claim that a thing’s
complexity is irreducible just adds another, separate claim requiring justification.
An argument from so-called irreducible complexity has the same problem as any argument from
design. The claim that a thing’s complexity cannot have – or is unlikely to have – come from natural processes combining simpler things must be demonstrable in each case.
Some arguments from design claim that a thing’s structure and function – especially if it is complex and supposedly irreducibly so –
is evidence for the intelligence of the design, and therefore of the designer.
But the modifier intelligent implies a contrast with non-intelligent design. Unless we
know what non-intelligent design is – and how it differs from intelligent design – the nature of intelligent design is unclear. And, of course, if there is no such thing as non-intelligent design, the expression intelligent design makes
no significant distinction.
If the expression non-intelligent design merely refers to naturally occurring structures and functions, the expression intelligent design
just adds another, separate claim requiring justification.
But usually, the claim that a design is evidence for intelligence is implicitly a claim about the nature of the designer. It
usually implies agency, intention or purpose, and (at least) intellectual power.
7 Probability: fine-tuning
Some arguments from a design to the existence of a designer are probabilistic, claiming that, because a thing is unlikely to have come about naturally, that makes it reasonable to believe it was designed.
For example, the so-called cosmological fine-tuning argument is that our universe had to have specific properties for it to exist at all, and to permit life to emerge; that its having those properties was highly improbable;
and that, therefore, it is reasonable to conclude our universe was fine-tuned by a designer.
But to calculate the probability of an event occurring, we need information. The more complete
the information, the more useful the calculation. And the more unjustified assumptions we make, the less useful the calculation.
Unless we know the possible outcomes, and the factors that
have or had a bearing on the outcome, we cannot calculate the probability of any actual outcome. And, of course, if all the possible outcomes are equally probable, the probability of any one outcome is the same as any other, how ever improbable it seems.
The cosmological fine-tuning argument fails because we lack the required information to calculate the probability of our universe being as it is.
An argument from a design to a designer is causal: this effect is evidence for the existence of this cause. Other examples include: this
made thing is evidence for a maker; and this creation is evidence for a creator.
We seem to be products of, and immersed in, natural causation. We try to explain features of reality by
tracing natural effects back to natural causes. We can do this because we have information about such causes and effects. And our natural explanations can have predictive power – so they can be useful.
But a causal explanation works only if there is evidence for the existence of the cause, and how it caused the effect. The absence of evidence may not mean the explanation is incorrect. But it does mean that to believe it is correct is irrational.
In other words, we must show why a thing is evidence for the existence of a designer or maker of that thing. And if we have no evidence for the
existence of that designer or maker, or for how it designed or made that thing, an argument from design is unsound.
9 Claims and evidence
It is important to distinguish between a claim and the evidence for the claim. A claim about a feature of reality is true if it correctly asserts that feature of reality, given the way we use the words or other signs involved.
But there must be a feature of reality in the first place.
An argument consists of one or more claims that supposedly justify its conclusion. But an argument is not evidence for its own
conclusion. For example, an argument from a design to the existence of a designer is not evidence that there was a designer. Claims and arguments are completely different from evidence.
such as this thing exists, or this event occurred, require objective justification in the form of evidence. What counts as evidence may be open to rational debate involving more claims and arguments. But this need not lead to an infinite
regress undermining our knowledge. That we can always say more does not mean we can never say enough.
A claim is only evidence for the belief of the claimant. For example, if someone claims
to have been abducted by aliens, that is not evidence that an alien abduction has occurred. It is merely testimony, which consists of a claim requiring objective justification.
is no evidence to support a claim of alien abduction, that may not mean the claim is false. But it does mean that to believe the claim is true is irrational.
10 Theistic arguments
There have been many theistic arguments from design to the existence of a god who designed and created our universe and the things in it. Traditionally, these were
called teleological arguments.
To generalise, a theistic argument from design makes a series of claims, each of which requires objective justification. The number and expression
of these claims has varied, but here are some representative examples.
1 This thing has been made to a design.
To our knowledge, things made to a design are evidence for the existence of a designer and maker.
3 The complexity of this thing’s structure or function means it cannot be, or is
unlikely to be, the un-designed product of natural processes.
4 This thing must have been, or is likely to have been, the product of non-natural causation.
5 The only non-natural cause intelligent and powerful enough to have designed and made this thing is a god.
The refutations of these claims have been
equally many and various. But here are some representative examples, in no particular order.
1 Though there have been many claims, there seems to be no evidence for the existence of a
god, or any other non-natural thing, nor for how such a thing designed and made our universe and the things in it.
2 We have some provisional knowledge of natural causation, based on evidence.
But there seems to be no evidence for non-natural causation. That may not mean claims of non-natural causation are false. But it does mean that to believe such claims are true is irrational.
To say a naturally occuring thing is like a designed and made thing is to make an argument from analogy. If such an argument ignores material differences, the analogy is false, or at least unconvincing.
4 The claim that a thing or event cannot have had, or is unlikely to have had, a natural cause, requires objective justification in each case.
5 To say that, if we do
not know the natural cause of a thing or event, the cause must be non-natural, is to make an argument from ignorance. The absence of a rational explanation does not make an irrational one viable.
8 March 2018