Critical Thinking Lecture 9:

Science, Pseudo-Science & Non-Science

9.1 What is Science?

In the US for the past few years there has been controversy raging over the

status of Intelligent Design Theory and whether it should be taught in school science

classes. The US has a constitutional ban on the teaching of religion in State schools,

so a large part of the political issue concerns whether Intelligent Design Theory is

science or not. This is a particular instance of a really interesting question concerning

the nature of science and the difference between science, pseudo-science and non-

science. We will consider this particular question and its more general counterpart, as

well as related questions: Should scientific explanation be privileged? If so, why?

How much can science explain? When are non-scientific explanations appropriate?

Science aims to discover the way the world is and explain why it is how it is.

Scientific claims, then, are descriptive claims and explanatory claims. Scientists use a

distinctive but fairly varied method that includes a combination of some or all of the

following:

the framing of hypotheses

the testing of hypotheses through observation and experiment

the duplication and verification of other scientists' experimental results

the use of mathematical models

the use of measuring instruments and other investigative technology

open argument when there is disagreement

While all scientists use some combination of these methods, the various sciences are

divided up according to subject matter, e.g. geology is the scientific study of the

Earth's crust; physics is the scientific study of fundamental particles, forces, space and

time; biology is the scientific study of living things, psychology is the scientific study

of mind and behaviour.

Since the Scientific Revolution in the 16th and 17th centuries, scientists have

been spectacularly successful in explaining many things that had previously been total

mysteries. e.g. The structure of the solar system, the mechanism of biological

inheritance, the cause of many illnesses, the cause of earthquakes. Scientific

discoveries have also allowed us to construct new technologies that fill the modern

world. e.g. cars, computers, televisions, artificial hips, etc. This success might lead us

to think that science can explain everything. Is this the case?

9.2 What Science Can't Do

There are many very important questions that science cannot answer.

Philosophers tend to be more aware of this than others, as many of these are questions

that we try to investigate philosophically rather than scientifically. e.g.

Normative questions: Questions about what to do. There are several different

kinds of normative questions. Some concern rationality and epistemology, e.g. What

should I believe? When should I seek more evidence? Note that scientists rely on

implicit answers to these questions whenever they do science, but they are not

themselves questions that can be investigated scientifically. Other normative

questions concern morality. What morally ought I do? Should I give money to

charity? Should I ever tell lies? Should I use animals in research? Science does not

address these questions. It tells us the way the world is, not the way the world should

be.

Evaluative questions: Questions about what is good or bad, admirable and

excellent or deplorable and deficient. Again, there are several kinds of evaluative

questions, including epistemic, moral and aesthetic. What makes a theory a good

theory and what makes a theory a bad theory? What is justification? Is courage

always morally admirable? What is just society? Who deserves to have the right to

vote? Is the Renzo Piano building in Sydney beautiful?

Questions about meaning: What does the word "natural" mean? How do

words and sentences come to have meaning?

Non-empirical questions: e.g. Some non-empirical questions are questions

concerning maths and logic. Note that there definitely are mathematical and logical

facts or truths, and that we definitely have objective mathematical and logical

knowledge. (Some people might describe maths and logic as weird kinds of science.)

Some non-empirical questions are questions about what happens in some hypothetical

unobservable realm that has no observable effect on our own, e.g. a separate afterlife.

Others are metaphysical questions, e.g. about the nature of causation, or about the

nature of particulars and universals, in which the disputing parties agree that all

observable facts would be the same regardless of which theory is correct.

Questions about the subjective character of experience; e.g. What is it like

to be a bat? What is it like for a colour-blind person to see red-green? We can answer

questions about the nature of our own experience through introspection, so these are

not non-empirical questions. Nonetheless, we cannot answer these questions

scientifically, because we cannot observe another person's experience. There can be

no objective data on these issues.

How might scientists respond to these claims about the limits of scientific

investigation?

One response is to argue that science can answer these questions (or can

answer some subset of them). Strictly speaking, I think this is not true. What is

certainly true is that science can help us to answer some of these questions by

showing us what causes what, and hence which are the likely effects of various

courses of action. Ignorance of the scientifically accessible facts can prevent us

from making correct decisions about what we should do. e.g. Some normative and

evaluative disagreements turn on the empirical question of what is the likely outcome

of certain courses of action. Suppose that we agree that we ought to act so as to

reduce poverty, and some people think we can do so by giving money to the poor

while others think we can do so by not giving money to the poor. In this dispute,

knowledge of the effects of those two policies will help us to decide what we ought to

do, and the best way to acquire such knowledge is through the social sciences,

including economics.

The basic questions in these domains, though, cannot be answered by

science. e.g. Should we act so as to reduce poverty? Or, should we confiscate the

property of the rich, if that is the best way to reduce poverty? We often should

appeal to science in order to help us to answer normative and evaluative

questions, but science alone is not sufficient to answer them.

Another possible response to the purported limits of science is offered by

logical positivists, who maintain that science can get at all of the facts, but to deny

that there are any facts concerning what is right or wrong, good or bad, no facts

concerning the subjective character of experience or God or the afterlife.

(Logical positivists say that there are lots of true claims concerning maths and logic

and meaning, but that such claims are tautologies, and hence do not express facts.)

If the logical positivists are right, then there is no point in arguing about

whether God exists or whether going to war is wrong. For the purposes of this course,

let's note that we do argue about these things, and we think that they are some of the

most important arguments we ever have. We think that we have been mistaken about

some of these things in the past. e.g. I used to think that homosexuality was wrong,

and now I see that I was mistaken in holding that view. This suggests that there are

facts in this domain, and that some kind of knowledge in these domains is possible.

Another possible response to the purported limits of science is to claim that

there are facts in these domains, but that we cannot ever know what the facts are, and

hence that there is no point trying to find out what they are. In this case, all useful

inquiry is still scientific inquiry because all accessible facts are accessible only via

science. Science can answer every question that is answerable.

This is obviously not true with regards to maths and logic. Why suppose that

science is the only way in which we can get at the facts? There are other forms of

inquiry as well.

The best response that scientists can make to the arguments concerning the

limits of scientific inquiry is to accept those limits and to defend the excellent

achievements of science within the domains to which is does apply. Science has given

us unparalleled success in predicting and explaining events. To admit that science

has a limited domain is not to devalue science, nor to undermine the power or

authority of science in the domains to which it does apply.

9.3 Science and Disagreement

Obviously, though the domain of science is very broad. Scientists attempt to

tell us what there is in the world, how the world works, and why the world is as it is.

Thus, the claims made by scientists sometimes clash with the claims made by people

from outside of science. What should we do when scientists disagree with another

source of information, such as religion or history or tradition?

Sometimes people respond to such clashes by arguing that science and other

sources of information are equal in the relevant respects, so that we have no reason to

favour science. e.g. Some people say that science is a religion just like the other

religions, or that science is a matter of faith, so we have no reason to privilege

scientific claims over religious claims.

Is science a religion? No, in part because religion is partly defined by its

subject matter - the sacred, the divine - and in part because the method of inquiry in

science is very different to the method of inquiry in most religions. Religious inquiry

is varied. It often relies on authority and sacred texts, but it can also include

straightforwardly philosophical argument (e.g. Aquinas) and "natural theology",

which makes an inference to the best explanation from the explanandum of world to

the existence of the most likely explanans - God. But almost all religious people who

employ these philosophical styles of argument also accord a significant role to

scripture as a source of knowledge about God and the world.

Is science a matter of faith? There are different senses of the word "faith".

To have faith in something can mean to trust it and rely on it, but to believe

something on the basis of faith means to believe it despite a lack of evidence for its

truth. Some religious people have faith in God, in the first sense, but think that there is

very strong evidence for the existence of God, so they do not believe on the basis of

faith, in the second sense. In contrast, some people have both kinds of faith in God.

Scientists have the first kind of faith in science, but they do not believe in science on

the basis of faith. They cite strong evidence that science reveals the way the world

works, e.g. evidence of our increased ability to predict and control events due to

scientific theories. Thus, it is misleading to claim that science is a matter of faith, that

there is no reason to trust in science, and that there is no evidence that favours a

scientific explanation over a non-scientific explanation.

In some cases it is very easy to see that a scientific claim is stronger than

competing religious, historical or traditional claims. Sometimes we can do it by

observation. e.g. The claim that the rain is caused by our sacrifices to the Rain

God is easily disproved by ceasing the sacrifices and noting that it still rains.

In some cases, though, it is harder to find a predictive difference between

competing scientific and non-scientific explanations. This is often true when the

events to be explained are one-off historical events. e.g. The creation of the universe

and the creation of species as described in Genesis in the Bible and as described by

physicists and biologists. In such cases we must consider which explanation fits better

with the observed facts. As we shall see, there can be deep disputes over this.

9.4 Are All Scientific Claims Correct?

Critics of a particular scientific theory often point out that we know that

scientists have been wrong in the past. e.g. Newton's physics was very widely

accepted, but then it turned out to be rejected after Einstein's theory of relativity. Does

the fact that scientists have been wrong show that we ought not accept the claims

of individual scientists? Does the fact that the scientific consensus has been

wrong show that we ought not accept the scientific consensus?

There is an important conclusion that we ought to draw from these facts. It is

that scientists, like everyone else, are fallible, and that we should hold open the

possibility that their claims are false. It is possible to have very good evidence for a

theory, even though that theory turns out to be false. But the fact that science is

fallible does not give us a reason to reject specific claims made by scientists. As we

have seen earlier in the course, a general sceptical worry should not lead us to reject

specific claims for which evidence is being offered. Note that exactly the same

general sceptical argument can be directed against every group, not just against

scientists. Thus, if it were a good argument, we should not accept the claims of

scientists, OR the claims of priests, OR the claims of historians, OR the claims of

philosophers, because members of all of those groups have made false claims.

When scientists put forward a theory, they are not asking you to accept it

merely on the basis of the fact that it is put forward by scientists. Scientists offer

evidence that the specific theory is true, and the appropriate response is to

evaluate that evidence as best we can and form our beliefs accordingly. The fact

that a theory is accepted by the scientific community might give us an extra reason to

believe that the theory it is true, although such a reason is obviously defeasible (i.e. it

might be overridden by other facts, or might dissolve in light of new information).

"Scientific" is not a synonym for "true" or "well-justified". Obviously, lots of

scientific theories have been incorrect, and it is very likely that some currently

accepted scientific theories will also turn out to be incorrect. In some cases, there is

no consensus amongst the scientific community. What should we do when scientists

disagree with each other? As in the case where scientists agree, we should evaluate

the evidence they offer as best we can and form our beliefs accordingly.

9.5 Science and Non-Science

Some theories are scientific theories that have been proved to be true. e.g.

Matter can be converted into energy, e = mc2. Other theories are scientific theories

that have been proved to be false. e.g. Light waves travel through an ether that fills

all of space. Character is revealed by the shape of a person's head (phrenology).

Some theories are not scientifically generated but are scientifically testable. e.g.

The rain is caused by our sacrifices to the Rain God.

The entire surface of the Earth was covered by water in the flood described in the

Book of Genesis.

Angles and Saxons invaded Britain and displaced the native Britons, so most of the

current English are the descendants of Anglo Saxons (an historically generated claim

that has been scientifically tested via DNA testing and disproven).

Other theories are not scientifically generated theories and are not scientifically

testable. e.g. That we have a perfect duty not to tell lies, and an imperfect duty to help

others.

The fact that a theory is not a scientifically generated theory and is not

scientifically testable does not in itself imply that there is something wrong with the

theory. e.g. A moral theory, which tells us which things are good and which actions

are right, which things are bad and which actions are wrong, is not a scientific theory,

but that is perfectly fine, because fundamental moral questions are not within the

domain of science.

There does seem to be a problem, though, when a theory appears to be within

the domain of science, in that it makes descriptive and explanatory claims about the

world, but is not scientifically testable. Such a theory should be scientifically testable,

but it is not. When such theories are presented as if they were scientific, we call them

pseudo-science. The philosopher Karl Popper offered a famous and influential

account of the difference between scientific and pseudo-scientific theories (or

scientifically testable theories and those that are not scientifically testable). According

to Popper, Marxism and Freudian psychology are presented by their proponents as

science, but neither are proper scientific theories.

Surprisingly, Popper claims that the reason that Marxism and Freudian

psychology are not scientific theories is that both theories do too good a job of fitting

with the observed facts. Traditional Marxists claim that history inevitably moves

through economic stages from feudalism to capitalism and finally to socialism. It

seems that Marxism generates predictions that can be tested against historical events.

However, a feature of the theory is that the progress towards socialism is not linear

and direct, but is dialectical in structure. Thus, even if a society moves from socialism

to capitalism, Marxists can say this fits with their theory, as it is just a dialectical step

that will eventually be followed by a permanent move to socialism.

Freudians posit lots of unconscious mechanisms that explain our behaviour.

e.g. Oedipus complex (a desire to kill your father and have sex with your mother). But

some people do not behave as if they want to kill their fathers. How can this fit with

Freudian theory? Freud posits another unconscious mechanism called "reaction

formation", which causes people to repress their desires and do the opposite of what

they really want to do. Thus, the Freudian claim that every man has an Oedipal

complex fits with all observed behaviour.

Popper rejects the view that theories which fit with all possible observations

are thereby convincing and well-confirmed. Rather, they are not proper scientific

theories. The right kind of theory, according to Popper, is a theory that makes

falsifiable claims. A claim is falsifiable if it would be shown to be false by some

possible observations. e.g.

The claim that all ravens are black is falsifiable, because the observation

of a white or pink raven would show that it is false.

The claim that Virgos might meet the man of their dreams in the coming

month are not falsifiable: if they do meet that man, the claim is true, but

if they don't meet that man, the claim could still be true.

The psychologist Bertram Forer conducted a famous experiment which

demonstrated that the problem with astrology was not that its star sign descriptions

did not apply to people who those particular star signs, but that the description for any

star sign applied equally well to everyone. He gave an "individually tailored

astrological description" to each of the subjects in the study, after which we asked the

subjects how well the description fitted them. Here is the description:

You have a need for other people to like and admire you, and yet you tend to

be critical of yourself. While you have some personality weaknesses you are

generally able to compensate for them. You have considerable unused

capacity that you have not turned to your advantage. Disciplined and self-

controlled on the outside, you tend to be worrisome and insecure on the inside.

At times you have serious doubts as to whether you have made the right

decision or done the right thing. You prefer a certain amount of change and

variety and become dissatisfied when hemmed in by restrictions and

limitations. You also pride yourself as an independent thinker; and do not

accept others' statements without satisfactory proof. But you have found it

unwise to be too frank in revealing yourself to others. At times you are

extroverted, affable, and sociable, while at other times you are introverted,

wary, and reserved. Some of your aspirations tend to be rather unrealistic.

The problem is that this description fits virtually everyone pretty well, and that people

who believe that it has been written especially for them are even more likely to say

that it is accurate. What seems like a detailed an specific description is actually so

broad and vague that virtually everyone identifies with it.

Popper claims that all theories that are genuinely scientific make falsifiable

claims. Some such scientific theories have actually been falsified. e.g. Phrenology led

to predictions that were falsified, so phrenology was a scientific theory but an

incorrect scientific theory. Other theories, including Marxism and Freudian

psychology, count as pseudo-science because the theories are unfalsifiable.

Note that claims can be falsifiable yet unfalsified, because no actual

observations have shown them to be false. According to Popper, the scientific theories

that we should accept are those that make bold, falsifiable predictions but have been

tested and not yet falsified. e.g. Einstein's theory of relativity made a bold prediction

that light would be bent by a gravitational field. This was tested in 1919 via

observations during a solar eclipse, and the prediction was vindicated. Hence,

Einstein's theory remains unfalsified.

Popper is an inductive sceptic, so he thinks that we can never know for sure

that a scientific theory is true. Popper thinks that a form of deductive inference

(modus tollens) lies at the heart of scientific knowledge.

If all ravens are black, then we will never observe a black raven.

We have observed a non-black raven.

Therefore, not all ravens are black.

Popper thinks that via this argument we can know that many scientific theories

are false. This makes it seem as science is always a negative exercise: ruling theories

out rather than discovering the true theory. Yet Popper thinks we should believe

scientific theories that are falsifiable, well-tested, and as yet unfalsified. It is not clear

whether Popper's inductive scepticism is warranted. Nonetheless, his point about

unfalsifiable theories is very important.

9.6 Is Popper Right?

Popper's account of the difference between science and pseudo-science has

been deeply influential, but is still contentious. One of the most significant objections

is that many scientific theories that we now think are very clearly true did not fit with

some observations in the past. If we had followed Popper's rule and rejected a theory

that clashed with an observation, then we would have rejected these true theories. e.g.

Copernican astronomy suggests that the Earth moves around the Sun but the stars do

not. This leads to the prediction that the apparent positions of the stars should change

through the year as we move closer towards some and further away from others - a

phenomenon called stellar parallax. However, stellar parallax was not observed. The

positions of the stars remain constant throughout the year. This observation seems to

falsify Copernican astronomy. But it would have been a terrible mistake to reject the

Copernican theory on these grounds.

The reason that we should not have rejected Copernican astronomy is that the

apparent falsifying observation was not really a falsification of the theory. The stars

are so far from the Earth that the parallax is undetectable without sophisticated

telescopes and measuring instruments. What appears to be a falsifying observation

might itself be misleading. It can be better to hold onto a scientific theory in the face

of apparently disconfirming evidence, and hope that the evidence can be explained

away in future.

Sometimes the first premise in Popper’s deductive argument is false. In this

case perhaps we need to make our scientific theory more complex, and then we will

see that the truth of the theory is compatible with the observation. Alternatively,

perhaps we just need to think through the implications of our theory more clearly, and

we will see that the theory fits with the observation. E.g.

If a creature has evolved by natural selection then it must be totally selfish, and

never help others.

We observe that human beings do help others.

Therefore human beings have not evolved by natural selection.

This argument has the kind of form that Popper recommends. Does it really

show that Darwinism is false? It does not. The first premise of the argument is a false

claim about what is implied by Darwinism (see the literature on the evolution of

cooperation).

Sometimes the second premise in Popper’s deductive argument is false. A

seeming observation of X might turn out to be mistaken.

If the Earth revolves around the Sun then through the year Venus should

sometimes appear bigger and sometimes appear smaller.

We observe that Venus remains a constant size throughout the year.

Therefore the Earth does not revolve around the Sun.

This argument has the kind of form that Popper recommends. Does it really

show that Copernicanism is false? It does not. The first premise of the argument is

true (so long as by "appears" we do not mean "appears to the naked eye"). The second

premise is false, as Galileo discovered by using the telescope.

This is the case with stellar parallax as well. The stars are so far from the Earth

that the parallax is undetectable without sophisticated telescopes and measuring

instruments. What appears to be a falsifying observation might itself be

misleading. It can be better to hold onto a scientific theory in the face of apparently

disconfirming evidence, and hope that the evidence can be explained away in future.

From this dispute in philosophy of science we can draw two important

conclusions:

We should be wary of theories that are designed so as to fit with all

possible observations. Such theories are unfalsifiable, and not scientific.

We should be wary of rejecting an otherwise well-confirmed scientific

theory simply because there are a few observations that apparently falsify

the theory. Sometimes the observations themselves are misleading, and

sometimes the interpretations of the observations are misleading.

Unfortunately, these two conclusions are in tension. It is better that we recognise this

tension and the subsequent difficulties that we have in assessing scientific theories,

rather than pretend that there are simple rules for determining whether a theory is

scientific and whether a theory is true.

9.6 Biological Explananda

The dispute between Darwinians and Intelligent Design theorists illustrates

this problem. Both theories are aimed at explaining the same facts about the

biological world, and the explanations offered are very different. Darwinians say that

complex plants and animals evolved gradually via an unguided process of natural

selection, whereas Intelligent Design theorists say that plants and animals must have

been designed and created in their complex form by an intelligent being. Intelligent

Design theorists usually believe that God is the intelligent designer, but they try to

separate that claim from the "scientific" part of their theory. Thus, most Intelligent

Design theorists are Creationists, but in the context of Intelligent Design theory they

do not call only evidence from religious texts to support their view. Intelligent Design

theorists argue that their theory is both scientific and true.

Both Darwinism and Intelligent Design are the result of arguments to the best

explanation. In order to assess them, we need to fix on what needs to be explained,

and then consider which of the theories offers a better explanation.

Biological Explananda:

* The origin of life - Where did plants and animals come from? Who or what

made them? By what process were they formed?

* Apparent design - How can we explain the fact that organisms contain parts

that are intricately and cleverly arranged to perform useful functions. e.g. the eye,

with its pupil, lens, etc. seems to be purposefully put together in order to allow us to

see. These parts all fit together into a coherent functioning whole. Why?

* Adaptive fit - why do organisms have traits which are particularly suited to

their environments. e.g. Why do polar bears have warm coats? Why do anteaters have

long, thin snouts?

* Apparent change - Fossil evidence suggests that many species no longer

exist (e.g. dinosaurs), that some species have came into existence later than others

(they are not found in older rocks), and that many species appeared to have undergone

change over time, and that more complex organisms appear later in the fossil record.

Why have some species changed over time, why have some remained the same? Why

have some species become extinct and others arisen later on? Why is there an increase

in complexity over time?

* Embryonic weirdness - e.g. Human embryos have tails, gills, etc. at some

stages of their development * Vestigial organs/limbs - Why do dolphins and whales have useless bones in

their bodies at the place where land-mammals' back limbs would be? Why do humans

have a useless (and dangerous) appendix? Why do lizards which live in utterly dark

caves have vestigial non-functional eyes?

9.7 The Darwinian Explanation

Darwin claimed that complex organisms evolved via natural selection. The Three conditions required for Evolution by Natural Selection (illustrated by an

easy example):

(1) phenotypic variation - there must be variation in a population for natural

selection to occur. e.g. some rabbits have slightly lighter winter fur than others.

(Again, variations may be of bodily form or of instinctive behaviour.)

(2) which affects reproductive success - this variation must have a

differential affect on reproductive success, i.e. organisms which possess the unusual

trait must do better or worse (on average) than those who lack it. e.g. rabbits with

lighter winter fur are less likely to be spotted by predators, and hence have a greater

chance of surviving the winter and reproducing. Over the course of their lives, they

have more offspring than darker rabbits.

(3) variations are inherited by offspring - the offspring of parents who

possess the unusual trait are (on average) more likely to possess that trait too. The

variation is "heritable". NB What causes the inheritance is irrelevant; so long as there

is some positive correlation between parent and offspring, the process of natural

selection can operate.

Why is each condition essential?

Without (1) every organism is the same. There is no difference in virtue of

which one can be selected over another. All rabbits will be the same shade.

Without (2) the differences between organisms don't make a difference to

their respective reproductive capacities. Whiter rabbits will do no better than darker

ones at producing offspring. Natural selection can't see these differences.

Without (3) even if whiter rabbits have more offspring than darker ones, the

babies of whiter rabbits will not themselves be more likely to be white. Hence, the

proportion of white rabbits in the population will not grow. Natural selection can see

the differences but the selection cannot accumulate - the slate is wiped clean at each

new reproductive stage.

One of the catchphrases used by Darwinians is the "survival of the fittest".

What does this mean? Some organisms possess traits which make them fitter, i.e.

stronger, better suited, hardier, more resourceful, less frail. Fit organisms will (on

average) have longer life spans, but this doesn't get at the significance of "survival of

the fittest". Those organisms in a population which are fitter than others are better

able to survive and reproduce than their counterparts. Hence, there will come to be a

greater number of their offspring in the population. If their offspring tend to inherit

the trait that increases their fitness, then, bit by bit, that trait will become dominant

across the population. Thus, evolutionary change has occurred. Darwin claimed that

the huge changes we see in the fossil record are accumulations of small changes due

to natural selection.

How does the Darwinian mechanism explain the explananda?

* Apparent design - How is it that organisms consist of an intricate

arrangement of complex parts, unless they are the product of an intelligent designer?

Darwin says that this arrangement is built up step by tiny step over vast periods of

time. e.g. a light sensitive cell can give an advantage to an organism, and will be

selected. Variations on this - a clump of cells, a clump of cells in a fold to increase

density, a circular layer of cells at the back of a pin-hole camera style cavity, a pin-

hole camera behind a clear protective barrier, the fluid in the cavity differentiates into

a lens - will each be selected, and come to predominate. Thus, apparent design

requires no designer, just lots of accumulated incremental advantages over a long

period. God is not required.

* Adaptive fit - Organisms are well-suited to their environments because the

environmental conditions play a huge part in determining respective fitnesses of the

organisms. Any type of organism slightly better suited to its conditions will have a

reproductive advantage, and will be selected. Over time, this will lead to the evolution

of complex ecosystems full of inter-connections and adaptations. e.g. rabbits in snowy

climates will have white fur in winter.

* Apparent Change - Darwin has a great explanation for the change that is

apparent in the fossil record. This change is evolution in progress. Given the pressure

of natural selection, you would not expect all species to remain the same over time,

and you would expect complexity to increase gradually.

* Embryonic weirdness & Vestigial Organs - These are not the kind of

features you would expect to find in creatures designed by God, but they are just the

kind of features you'd expect in species that are gradual modifications of other

species.

Darwinism does not explain the origin of life.

9.8 Intelligent Design

Intelligent Design theory suggests that an intelligent designer created

organisms in their present complex form. Thus, Intelligent Design theory is a

competitor to Darwinism. Moreover, Intelligent Design is presented as a science. NB

Many people who are religious, and who believe that there is an intelligent creator of

the universe, do not believe Intelligent Design theory.

How does Intelligent Design Theory account for the explananda?

Intelligent Design theorists have an neat explanation of apparent design and

adaptive fit: they think that apparent design is actual design, and that the designer

designed creatures so that they would be suited to their specific environments. In fact,

the ID theorists argue that Darwinians cannot explain the structured complexity of

many features of organisms, and that only a designer could have produced such

complexity. Darwinians must respond by showing how a complex organ or process

which contains many necessary parts can evolve bit by bit. They do offer such

explanations.

How do ID theorists explain the apparent change in species over time? They

could argue that these apparent changes are merely apparent (i.e. there is merely an

illusion of change), and that the designer created organisms all at roughly the same

time and in their current form (and maybe some died out). This does not fit well with

the geological evidence. Alternatively, ID theorist could argue that God created

organisms in their current form but not all at roughly the same time. Rather, he

designed and created the simpler ones first, and then created more complex ones later

on. This is certainly possible, but is it an ad hoc response?

How do ID theorists explain embryonic weirdness and vestigial organs?

They simply have to say that the designer designed creatures that way. They might try

to make this sound more plausible by looking for functions possessed by vestigial

organs, but this will be pretty difficult.

Obviously, the danger with ID theory is that it seems to be unfalsifiable.

Whatever we observe in organisms fits with the theory, because the designer could

have designed things in that way. If the theory does not make falsifiable claims,

Popper would say that it is not a scientific theory.

The following text in italics is from the Intelligent Design and Evolution

Awareness Centre website http://www.ideacenter.org. (I have deleted some sections

to make it shorter.) It is a nice example of arguments for both the view that Intelligent

Design is a science and that Intelligent Design is true.

FAQ: Does intelligent design make predictions? Is it testable?

At the heart of science is observations, which is what forms the beginning of

the scientific method. These observations allow us to make a hypothesis

which make testable predictions about what we would expect to find if that

hypothesis were true.

Putting Intelligent Design to the Test:

Intelligent design theorists begin with their theory with observations about

how intelligent agents act when designing, to help them understand how to

recognize and detect design:

Ways Designers Act When Designing (Observations): Intelligent agents ...

(1) Take many parts and arrange them in highly specified and complex

patterns which perform a specific function.

"Experience teaches that information-rich systems … invariably result from

intelligent causes, not naturalistic ones. … Finding the best explanation,

however, requires invoking causes that have the power to produce the effect

in question. When it comes to information, we know of only one such cause.

For this reason, the biology of the information age now requires a new

science of design."

(Stephen C. Meyer, "The Explanatory Power of Design," in Mere Creation,

pg. 140 (William A. Dembski ed., InterVarsity Press 1998))

"Indeed, in all cases where we know the causal origin of 'high information

content,' experience has shown that intelligent design played a causal role."

(Stephen C. Meyer, DNA and Other Designs)

(2) Rapidly infuse any amounts of genetic information into the biosphere,

including large amounts, such that at times rapid morphological or genetic

changes could occur in populations.

"Intelligent design provides a sufficient causal explanation for the origin of

large amounts of information, since we have considerable experience of

intelligent agents generating informational configurations of matter."

(Meyer S. C. et. al., "The Cambrian Explosion: Biology's Big Bang," in

Darwinism, Design, and Public Education, edited by J. A. Campbell and S.

C. Meyer (Michigan State University Press, 2003)

(3) 'Re-use parts' over-and-over in different types of organisms (design

upon a common blueprint).

"An intelligent cause may reuse or redeploy the same module in different

systems, without there necessarily being any material or physical connection

between those systems. Even more simply, intelligent causes can generate

identical patterns independently: We do so, for instance, every time we sign

a bank check or credit card slip" (Nelson and Wells, Homology in Biology,

in Darwinism, Design, and Public Education, pg. 316, 318 (John Angus

Campbell, ed. Michigan State University Press 2003).

(4) Be said to typically NOT create completely functionless objects or parts

(although we may sometimes think something is functionless, but not

realize its true function).

These observations can then be converted into predictions about what we

should find if an object was designed:

Predictions of Design (Hypothesis):

(1) High information content machine-like irreducibly complex structures

will be found.

(2) Forms will be found in the fossil record that appear suddenly and

without any precursors.

(3) Genes and functional parts will be re-used in different unrelated

organisms.

(4) The genetic code will NOT contain much discarded genetic baggage

code or functionless "junk DNA".

These predictions can then be put to the test by observing the scientific data:

Table 3. Examining the Evidence (Experiment and Conclusion):

(1) Biochemical complexity / Laws of the Universe.

High information content machine-like irreducibly complex structures are

commonly found. The bacterial flagellum is a prime example. Specified

complexity found in the laws of the universe may be another.

Prediction of Design Met?: Yes.

(2) Fossil Record

Biological complexity (i.e. new species) tend to appear in the fossil record

suddenly and without any similar precursors. The Cambrian explosion is a

prime example.

Prediction of Design Met?: Yes.

(3) Distribution of Molecular and Morphological Characteristics

Similar parts found in different organisms. Many genes and functional parts

not distributed in a manner predicted by ancestry, and are often found in

clearly unrelated organisms. The "root" of the tree of life is a prime example.

Prediction of Design Met?: Yes.

(4) DNA Biochemical and Biological Functionality

Increased knowledge of genetics has created a strong trend towards

functionality for "junk-DNA." Examples include recently discovered

functionality in some pseudogenes, microRNAs, introns, LINE and ALU

elements. Examples of DNA of unknown function persist, but discovery of

function may be expected (or lack of current function still explainable under

a design paradigm).

Prediction of Design Met?: Yes.

In this manner, intelligent design is clearly testable as it observes how

intelligent agents act when designing (Table 1) in order to make predictions

about what we should find if an intelligent agent had been at work (Table 2) ,

and then goes out and tests those predictions to see if they are met (Table 3)!

9.9 Assessing Darwinism and Intelligent Design

Are the so-called predictions made by ID any different to the predictions made

by Darwinism?

Darwinians say that their own theory explains the existence of so-called

irreducibly complex structures, e.g. the eye.

A quote from "Devolution" by H. Allen Orr:

As biologists pointed out, there are several different ways that Darwinian

evolution can build irreducibly complex systems. In one, elaborate structures

may evolve for one reason and then get co-opted for some entirely different,

irreducibly complex function. Who says those thirty flagellar proteins weren't

present in bacteria long before bacteria sported flagella? They may have been

performing other jobs in the cell and only later got drafted into flagellum-

building. Indeed, there's now strong evidence that several flagellar proteins

once played roles in a type of molecular pump found in the membranes of

bacterial cells.

Behe [an Intelligent Design theorist] doesn't consider this sort of "indirect"

path to irreducible complexity—in which parts perform one function and then

switch to another—terribly plausible. And he essentially rules out the

alternative possibility of a direct Darwinian path: a path, that is, in which

Darwinism builds an irreducibly complex structure while selecting all along

for the same biological function. But biologists have shown that direct paths to

irreducible complexity are possible, too. Suppose a part gets added to a

system merely because the part improves the system's performance; the part is

not, at this stage, essential for function. But, because subsequent evolution

builds on this addition, a part that was at first just advantageous might

become essential. As this process is repeated through evolutionary time, more

and more parts that were once merely beneficial become necessary.

Darwinians also say that they can explain why some complex creatures

appear suddenly in the fossil record. The fossil record is patchy and highly

dependent on chance. But Darwinians will also argue that in many cases there is a

fossil record of the gradual development of complex creatures.

Darwinians will also explain why distantly-related organisms have similar

functional parts. If the functional part is really useful, it is possible that it will evolve

separately in distinct lineages. e.g. Wings in birds and bats, tail fins in sharks and

dolphins, eyes in humans and cockroaches and bees. But note that in these cases there

are often interesting differences between the functionally similar parts, e.g. orientation

of fins, structure of eyes. If the idea is that a designer would reuse existing designs in

many organisms, why are there such differences? Why didn't a designer slot in the

same kind of eye for all insects?

Darwinians also explain why most of the parts of organisms have functions. If

the parts were shaped by natural selection, then the parts contributed something to the

raising of the organisms' fitness, i.e. they have a function.

Showing that ID's so-called predictions are confirmed does not give us a

reason to favour ID over Darwinism, because Darwinism makes roughly the

same predictions on the specific points mentioned by ID theorists. Could we

distinguish the two theories by getting them to make different predictions and then

testing which predicts correctly?

Are there really clear predictions made by ID? Or are there merely

descriptions of what we know already about biology? Is this a case where prediction

plays little role and we instead have to assess the theories according to how well they

fit with the observed facts?

Does either Darwinism or ID make any falsifiable predictions?

Does Darwinism make any novel predictions or offer explanations of facts that

are not explained by ID? Some biologists say that it does. e.g. Darwinism explains

why there must be gradual development of complexity of life through the fossil

record. This generates a prediction: we will not find a fossil of a horse in Cambrian

rock. Such a find would falsify Darwinism, and that fact that we made no such find

seems to confirm the Darwinian account of evolution. Note that such a find would not

falsify ID theory.

Can ID theorists explain why fossils show animals getting increasing more

complex over time? A designing God could have created creatures in ascending order

of complexity like this, but why would he? Was he learning along the way?

Darwinians argue that it is ad hoc to claim that God created animals but did so in

ascending order of complexity, so that it looked as if they were evolving.

Can we know what an intelligent designer would design, and what methods he

would use, without knowing more about his aims? e.g. Is the aim of the designer to

make creatures that are nice to each other? Is the aim of the designer to make strong

and disease resistant creatures? Is the aim of the designer to make clever creatures?

Whose teeth did not decay? Were there limits on what the designer could accomplish?

ID assumes that designers do not include many things in their designs that do

not have functions. They typically do not create functionless parts. Is the ID theorists

claim a falsifiable prediction?

Suppose that the ID theorists are correct, and that designed objects typically

do not include parts that have no functions. What about the Darwinians' favourite

evidence: vestigial limbs and eyes, vestigial leg bones in whales, the appendix in

humans, the tail and gills on human embryos. These parts have no useful functions,

but they are easily explicable on the Darwinian account as being the remnants of

things that once did have useful functions in the ancestors of the current organisms.

Darwinians also draw on other examples of non-optimal design, e.g. the Panda's

thumb, which is not well-designed, but is good enough for some basic purposes. Why

would an intelligent designer who knows how to make a really good thumb give the

Panda a dud?

What will Darwinians say about the ID theorists' claim that junk DNA will

turn out to have a function? They might be happy to accept this. The standard

explanatory model in Darwinism is to suppose that a trait is an adaptation, and hence

has a biological function. Note that Darwinians have an explanation for why some

traits of organisms no longer fulfil their function - the environment has changed or the

organism has evolved (e.g. the appendix). Darwinians also can explain why there

could well be a lot of functionless junk DNA. They offer a gene-level selection story

which also fits well with difficult cases like meiotic driving genes. See your biology

textbooks for a detailed description.

Note, however, that the ID theorists' claim is couched in language that

makes it harder to falsify. Designers typically don't include parts that have no

function, so designed objects will not contain many of such parts. Thus, even if we

discover that there is plenty of functionless junk DNA, ID theorists can hold on to

their theory. As we have seen, this kind of unfalsifiability does not make a theory

stronger. In fact, it suggests that it might not be a scientific theory at all.

If Intelligent Design Theory were true, what else would we expect to observe?

Other evidence of the designer. Why doesn't the designer enter the debate and tell us

that he designed organisms?

Is Darwinism itself really falsifiable? Some critics accuse Darwinians of being

adaptationists, i.e. of assuming that every feature of an organism must be designed by

natural selection, and must have been fitness enhancing. Then Darwinians invent

“Just so” stories to explain what they have observed. But how then can we test

whether the Darwinian explanation was correct?

Darwinists offer possible means of testing which "Just So" stories are correct:

Corroborative evidence from DNA studies, which allows us to place organisms in

the phylogenetic tree.

Paleontological investigation of past environments.

This process of testing explanations is very difficult.