Download Astrology: A Case Study

Astrology
A Case Study
Rod Watkins
Version 1.1.1, 2017-03-23
Revision: 1.1.1 | Revision date: 2017-03-23
What is Science?
Science seeks explanations to satisfy the wonder. But so do other
human enterprises. The difference between science and other
enterprises that seek explanations of why things are the way they are
can be found in the sorts of standards that science sets itself for
what will count as an explanation, a good explanation, and a
better explanation. The philosophy of science seeks to uncover those
standards, and the other rules that govern scientific methods.
— Alex Rosenberg
1. Constitutive question: What is a scientific explanation?
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2. Normative question: What makes a scientific explanation good and what makes one
scientific explanation better than another?
Answers
• The philosophers we will study this semester provide a unified account of scientific
explanations that answers both the constitutive and the normative questions.
• The theoretical and evidential basis for this account is:
◦ How scientists and others actually do judge an explanation to be good or that one
explanation is better than another, or even when a supposed explanation fails to in
fact be an explanation at all.
◦ General philosophical theories, especially theories about the nature, extent and
justification of knowledge—that is, epistemological theories.
Epistemology and Science
• We will return to the issue of the more general philosophical underpinnings of scientific
explanation later.
• The History can arbitrarily divided into two periods:
◦ The Early Modern Period (1600-1800 - Descartes, Locke, Berkeley, Hume, Reid, Kant)
◦ The Late Modern Period (1800-present) - Hempel, Popper, Kuhn among many others.
A Note on Our Methodology
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I shall not today attempt further to define the kinds of material I
understand to be embraced within that shorthand description [hardcore pornography]; and perhaps I could never succeed in intelligibly
doing so. But I know it when I see it, and the motion picture involved
in this case is not that.
— Justice Potter Stewart, Jacobellis v. Ohio 378 US 184 (1964)
Reflective Equilibrium
• Balances tutored intuition against coherent criteria of adequacy for a scientific
explanation.
• This balancing is an on-going process.
A Case Study
• So we shall begin by introducing astrology as a paradigmatic example of a pseudoscience
(in contrast to astronomy).
◦ If any account of pseudoscience leads to the inclusion of astrology amongst the
sciences, we will reject the account.
◦ By the same token, any account of pseudoscience leads to the exclusion of astronomy
amongst the sciences, we will reject as well.
Hines on Astrology
• Hines (Hines, 2003)) concludes that astrology is a pseudoscience on four bases:
◦ Historical stagnancy
◦ Logical incoherence
◦ Theoretical weakness
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◦ Empirical failing
Astrology’s History
• Ancient Mesopotamia saw the stars as a source of omens:
◦ When Mars approaches the star Shu.gi there will be uprising in Ammurru and
hostility; one will kill another.
◦ When Venus stands high, there will be the pleasure of copulation.
• Such omens were just some among many:
◦ If a woman gives birth to a pig, a woman will seize the throne.
◦ If a woman gives birth to an elephant, the land will be laid to waste.
• Given their content, they could hardly be based on empirical investigations (e.g.,
observing over many trials the outcome of post pig-birthing).
Background
• The first horoscope dates to April 29, 410 BCE
• Modern astrology was formalized (so to speak) in the second century CE by the
astronomer and astrologer Ptolemy.
• The Ptolemaic astrological system was accepted well into the late Medieval period and
has remained more or less unchanged since.
Astrology as Magical Thinking
• At the heart of Hines criticism of astrology is that it amounts to little more than magical
thinking.
• Let’s pursue the idea of magical thinking for a moment.
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Magical Thinking Defined
According to anthropologist Dr. Phillips Stevens Jr., “magical thinking
involves
several
elements,
including
a
belief
in
the
interconnectedness of all things through forces and powers that
transcend both physical and spiritual connections. Magical thinking
invests special powers and forces in many things that are seen as
symbols.” According to Stevens, "`the vast majority of the world’s
peoples … believe that there are real connections between the symbol
and its referent, and that some real and potentially measurable power
flows between them. (“Magical Thinking,” 2017) == A Sampling of
Magical Thinking
— Skeptic's Dictionary
• Law of Similarity: that things that resemble each other are also somehow causally
connected in a way not verifiable by scientific means.
• Law of Contagion: the belief that “things that have been either in physical contact or in
spatial or temporal association with other things retain a connection after they are
separated.”, e.g., relics of saints, psychic detectives.
Alcock on Magical Thinking
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Magical thinking is the interpreting of two closely occurring events as
though one caused the other, without any concern for the causal link.
For example, if you believe that crossing your fingers brought you
good fortune, you have associated the act of finger-crossing with the
subsequent welcome event and imputed a causal link between the
two. (Alcock, n.d.)
— James Alcock, Reading 1
Why Do We Think Magically?
• Enlightenment thinkers such as the Scottish philosopher David Hume (1711-1776)
believed that universal education and a steadfast commitment to rationality would rid
the world of magical thinking and superstitions.
• Sadly, it has not. Alcock offers an explanation for why that may be that is relevant to our
purpose.
Belief Engines
• We must bear in mind that we are fitted with a brain and nervous system that was
designed by a process driven primarily and relentlessly by reproductive success and not
discovering the truth.
• One needn’t believe only what is true and disbelieve only what is false to reproduce.
In Alcock’s Words
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It is because our brains and nervous systems constitute a beliefgenerating machine, an engine that produces beliefs without any
particular respect for what is real or true and what is not. This belief
engine selects information from the environment, shapes it, combines
it with information from memory, and produces beliefs that are
generally consistent with beliefs already held. This system is as
capable of generating fallacious beliefs as it is of generating beliefs
that are in line with truth. These beliefs guide future actions and,
whether correct or erroneous, they may prove functional for the
individual who holds them. Whether or not there is really a Heaven
for worthy souls does nothing to detract from the usefulness of such a
belief for people who are searching for meaning in life.
— James Alcock
Irrational Beliefs
• Rational as well as irrational beliefs are issued from this belief engine in a rather
automatic (though culturally conditioned) manner.
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Nothing is fundamentally different about what we might think of as
irrational beliefs — they are generated in the same manner as are
other beliefs. We may not have an evidential basis for belief in
irrational concepts, but neither do we have such a basis for most of
our beliefs. For example, you probably believe that brushing your
teeth is good for you, but it is unlikely that you have any evidence to
back up this belief, unless you are a dentist. You have been taught this,
it makes some sense, and you have never been led to question it.
— James Alcock
Belief Engine Components
• The learning unit
• The critical thinking unit
• The yearning unit
• The input unit
• The emotional response unit
• The memory unit
• The environmental feedback unit
Learning Unit
• The Learning Unit is one of the most important for our purposes.
• The manner in which this unit functions makes magical thinking a matter of normal
cognitive operation.
• And it has obvious selective advantage despite issuing in irrational beliefs on a reliably
regular basis.
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The learning unit is the key to understanding the belief engine. It is
tied to the physical architecture of the brain and nervous system; and
by its very nature, we are condemned to a virtually automatic process
of magical thinking.
— James Alcock
A Properly Functioning Learning Unit Errs
Our brain and nervous system have evolved over millions of years. It
is important to recognize that natural selection does not select directly
on the basis of reason or truth; it selects for reproductive success.
Nothing in our cerebral apparatus gives any particular status to truth.
— James Alcock
An Example
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Consider a rabbit in the tall grass, and grant for a moment a modicum
of conscious and logical intellect to it. It detects a rustling in the tall
grass, and having in the past learned that this occasionally signals the
presence of a hungry fox, the rabbit wonders if there really is a fox
this time or if a gust of wind caused the grass to rustle. It awaits more
conclusive evidence. Although motivated by a search for truth, that
rabbit does not live long. Compare the late rabbit to the rabbit that
responds to the rustle with a strong autonomic nervous-system
reaction and runs away as fast as it can. It is more likely to live and
reproduce. So, seeking truth does not always promote survival, and
fleeing on the basis of erroneous belief is not always such a bad thing
to do. However, while this avoidance strategy may succeed in the
forest, it may be quite dangerous to pursue in the nuclear age.
— James Alcock
Proper Functioning
• When functioning properly, the learning unit sets up associations between significant
events rapidly and in a manner that is lasting
• Example: touching a hot stove and being burnt
• Non-pairings of such events do not form such associations—a significant factor.
Poor Judgments
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Humans are very poor at accurately judging the relationship between
events that only sometimes co-occur. For example, if we think of
Uncle Harry, and then he telephones us a few minutes later, this might
seem to demand some explanation in terms of telepathy or
precognition. However, we can only properly evaluate the cooccurrence of these two events if we also consider the number of
times that we thought of Harry and he did not call, or we did not think
of him but he called anyway. These latter circumstances — these nonpairings — have little impact on our learning system. Because we are
overly influenced by pairings of significant events, we can come to
infer an association, and even a causal one, between two events even
if there is none.
— James Alcock
Alcock continues…
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Thus, dreams may correspond with subsequent events only every so
often by chance, and yet this pairing may have a dramatic effect on
belief. Or we feel a cold coming on, take vitamin C, and then when the
cold does not get to be too bad we infer a causal link. The world
around us abounds with coincidental occurrences, some of which are
meaningful but the vast majority of which are not. This provides a
fertile ground for the growth of fallacious beliefs. We readily learn
that associations exist between events, even when they do not. We are
often led by co-occurring events to infer that the one that occurred
first somehow caused the one that succeeded it.
— James Alcock
Critical Thinking Unit
• But all is not lost. Errors are still errors. And errors, insofar as they get things wrong, are
better to be avoided if possible.
• So we also have a means of correcting those errors: the Critical Thinking Unit.
Critical thinking as a means of selfcorrection
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The critical-thinking unit is the second component of the belief
engine, and it is acquired — acquired through experience and explicit
education. Because of the nervous-system architecture that I have
described, we are born to magical thinking. The infant who smiles just
before a breeze causes a mobile above her head to move will smile
again and again, as though the smile had magically caused the desired
motion of the mobile. We have to labour to overcome such magical
predisposition, and we never do so entirely. It is through experience
and direct teaching that we come to understand the limits of our
immediate magical intuitive interpretations. We are taught common
logic by parents and teachers, and since it often serves us well, we use
it where it seems appropriate. Indeed, the cultural parallel of this
developmental process is the development of the formal method of
logic and scientific inquiry. We come to realize that we cannot trust
our automatic inferences about co-occurrence and causality.
— James Alcock
One purpose of this course
• The improvement of our critical thinking skills is the central aim of this course and is
reflected in our broader philosophical understanding of what makes a scientific
explanation good.
• But more on this later.
So far…
• We have the means, the cognitive capacity, to learn of new causal associations (causal
patterns) found in nature (real or not).
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• We also have the means to correct those initial and automatic judgments of causal
connections.
• There are several other facilities of our nervous systems' that can affect this learning and
self-correction cycle.
Yearning Unit
Learning does not occur in a vacuum. We are not passive receivers of
information. We actively seek out information to satisfy our many
needs. We may yearn to find meaning in life. We may yearn for a
sense of identity. We may yearn for recovery from disease. We may
yearn to be in touch with deceased loved ones.
— James Alcock
• The effect of yearning can be to make fallacious reasoning even more likely.
The Input Unit
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Information enters the belief engine sometimes in the form of raw
sensory experience and other times in the form of organized, codified
information presented through word of mouth, books, or films. We
are wonderful pattern detectors, but not all the patterns we detect are
meaningful ones. Our perceptual processes work in such a way as to
make sense of the environment around us, but they do make sense —
perception is not a passive gathering of information but, rather, an
active construction of a representation of what is going on in our
sensory world.
— James Alcock
Receiving input is active (i.e., constructed)
Our perceptual apparatus selects and organizes information from the environment, and this
process is subject to many well-known biases that can lead to distorted beliefs. Indeed, we are
less likely to be influenced by incoming information if it does not already correspond to
deeply held beliefs. Thus, the very spiritual Christian may be quite prepared to see the Virgin
Mary; information or perceptual experience that suggests that she has appeared may be
more easily accepted without critical scrutiny than it would be by someone who is an atheist.
It is similar with regard to experiences that might be considered paranormal in nature.
• Such cognitive biases will be the subject of discussion several times in the coming weeks.
• But, as a first step, we will need to abandon the notion that the input to our cognitive
machinery is akin to the input to a recording device (i.e., photography, videography),
leaving a verbatum record of events recorded.
• Rather, perception is constructive.
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The Emotion Unit
Experiences
accompanied
by
strong
emotion
may
leave
an
unshakable belief in whatever explanation appealed to the individual
at the time. If one is overwhelmed by an apparent case of telepathy, or
an ostensible UFO, then later thinking may well be dominated by the
awareness that the emotional reaction was intense, leading to the
conclusion that something unusual really did happen. And emotion in
turn may directly influence both perception and learning. Something
may be interpreted as bizarre or unusual because of the emotional
responses triggered.
— James Alcock
• Strong emotional reactions affect the operation of the belief engine as well.
• In particular, strong emetions can affect our ability to perceive and critically think.
Memory Unit
• What goes for perceptual input goes for memory: it is also constructive.
Through our own experience, we come to believe in the reliability of
our memories and in our ability to judge whether a given memory is
reliable or not. However, memory is a constructive process rather
than a literal rendering of past experience, and memories are subject
to serious biases and distortions.
— James Alcock
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Environmental Feedback Unit
Beliefs help us to function. They guide our actions and increase or
reduce our anxieties. If we operate on the basis of a belief, and if it
"works" for us, even though faulty, why would we be inclined to
change it? Feedback from the external world reinforces or weakens
our beliefs, but since the beliefs themselves influence how that
feedback is perceived, beliefs can become very resistant to contrary
information and experience. If you really believe that alien
abductions occur, then any evidence against that belief can be
rationalized away — in terms of conspiracy theories, other people’s
ignorance, or whatever.
— James Alcock
• This is called belief persistence. Remember, false beliefs may be more functional than
true beliefs—e.g., The Secret. The fact that such beliefs are functional (in a very broad
sense) makes them resistant to disconfirmation by contrary evidence.
• We will return to this when we discuss confirmation bias and other errors of judgment.
The Upshot
• The upshot is hopefully now obvious:
◦ Magical thinking is how we have been designed by natural selection to think—to
quickly set up associations between events even though there may be no causal
basis for them whatsoever.
◦ Moreover, such beliefs, reinforced by the manner in which perception, memory,
desires, emotions, and environmental feedback function, will often be very hard to
change even in the face of rationally compelling evidence to the contrary.
• In short, we will believe where we do not have evidence and we will feel certain those
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beliefs are true.
Back to Astrology
• Astrology, we shall now see Hines argue, is a classic example of magical thinking.
◦ It sets up associations (e.g., between being born under the sign of Aries and being an
extrovert) that have no causal basis.
◦ Moreover, these beliefs are very resistant to change despite the historical, logical,
theoretical and empirical evidence to the contrary.
• One other lesson:
◦ If Alcock is right about us having a belief engine that functions as he describes, then
possessing irrational beliefs is to be expected.
◦ It is to be expected in everyone—even the most hardened scientist has the same
evolved belief engine we do and so will be prone to magical thinking.
◦ Thus, irrational beliefs are not the product of some character flaw or weakness of
will or willful blindness, but of a biological design.
Historical evidence of magical thinking
• Classical Greek Astrology
◦ Venus was the god of love and beauty, so those born under that sign are sensitive,
emotional and appreciate beauty.
◦ Mercury was the messenger of the gods (because it moved fast and was hard to see),
so those born under that sign are difficult to predict, deceitful but skillful. (Hines
206)
• Even the constellations that make up the zodiac are arbitrary.
Some preliminaries
• One of the problems with magical thinking is that it forms associations that have not
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been put to the test—that is, they have not undergone the process of critical evaluation.
• If astrology is merely magical thinking, we should expect then that when it has faced
cogent criticism, it would remain unchanged.
• In other words, a mark of scientific thinking is a critical responsiveness to the evidence;
magical thinking, by contrast, illustrates an hypocritical unresponsiveness to criticism
and contrary evidence.
• Astrology, by this criterion, again exhibits merely magical thinking for it has remained
relatively unchanged in form for 2500 years despite a wide range of evidence that
challenges its precepts.
On the evidence
• Hines notes that in the entire 2500 year history of astrology, “no astrologer has ever tried
to see if the hypothesized relationships between heavenly bodies and human behavior
really exist.” (208)
• This near total disregard for gathering positive evidence in favour of astrology extends
to the vastly accumulating negative evidence against astrology.
Supporting evidence
• The cases are rare, but Hines finds one: In 1970, Steven Schmidt proposed adding two
additional signs to the Zodiac (an idea well supported by the astronomical data).
• But when it came to the question of what behavioural traits are to be associated with
these new signs, Schmidt simply collected a list of people born under them and read off
some traits.
• Furthermore, the sample was not at all random or representative since it was a list of
famous movie stars, past presidents, politicians, etc.
Contrary evidence
• Because of what astronomers call precession, the location of the constellations in the
sky at a given time of the year has changed dramatically in the past 2500 years, so much
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that they are now almost a month off what they were.
• So someone born between March 21 and April 19 2500 years ago would have been born
under the sign of Aries as that was the constellation the Sun was in during that period.
• But if you are an Aries now, the Sun would almost certainly not be found in Aries, but in
Pisces.
• Yet horoscopes continue to be cast using the old, now incorrect, tables even though
astrologers are aware of precession.
Contrary evidence - the solar system
The ability to derive, test, and verify or falsify predictions is one of the
most important characteristics of science. (210)
— Hines
• Astrology claims there are seven heavenly bodies (minus the Earth): the Sun, the Moon,
Mercury, Venus, Mars, Jupiter and Saturn.
• Modern astronomy has proven there are two additional planets (and one plutoid)
present: Uranus (1781), Neptune (1846) and Pluto (1930).
• Astrology neither predicted nor verified the existence of these three additional heavenly
bodies.
• Astronomy, by contrast, did predict and verify their existence.
The discovery of Neptune
 https://www.youtube.com/watch?v=Q0camKgvAUs (YouTube video)
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Contrary evidence
mechanism
-
the
lack
of
a
• Question: What is the mechanism by which by which any alleged astrological influence
would occur?
• Newton and “action at a distance”.
◦ Gravity and tidal forces are far too weak to have any influence on human behavior.
◦ And we know for a fact that electromagnetic forces cannot be what is at work.
• By contact via emitted particles.
◦ But only the Sun emits particles.
The empirical evidence
• Even if we lack any theoretical account of how the heavenly bodies might affect human
behavior—even if, that is, we have no working hypothesis about how this could occur—
there is a prior question we should ask.
◦ Is there any need for such a hypothesis?
◦ Is there any evidence to support even a correlation, yet alone a causal relation,
between signs of the Zodiac and behavioral traits?
Consider an example
Consider:
• Working hypothesis: More extroverts are born under Aries than introverts.
• Null hypothesis: the number of extroverts and introverts born under Aries should be
about the same.
If our belief engine operates as Alcock theorizes, then we should not be surprised to find that
we are predisposed to find connections (between Aries and extroversion) where the
evidence, critically evaluated, shows there is none.
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Hines' example
Advertise in campus paper for individuals born between March 21 and April 19.
32 respond.
Each is given a personality test to detect whether they are introverted or extroverted.
Then we count up how many are of each type.
Possible distributions
16/16 – we judge no effect
32/0 – we judge a strong effect
18/16 – we judge the slight difference is just due to chance
21/11 – in this case things are not so clear. Is this due to chance or some non-chance factors?
How about 22/10?
Possible conclusions
• Untutored reliance on our belief engine would likely lead us to believe on the basis of the
both the 21/11 and 22/10 results that there is “something going on here”, so to speak.
• Tutored critical evaluation gives us criteria for choosing.
• Having learned the mathematical science of statistics, we know the result must be
statistically significant.
Statistical Significance
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…if a statistical analysis shows that a particular result would have
occurred by chance fewer than 5 times out of 100 (less than 5 percent
of the time, or 1 time in 20) the result is accepted as statistically
significant
— Hines, 214
As the likelihood that a result may have occurred as a result of chance decreases, the
statistical significance of that result increases.
!Chance
Row
Extroverts
Introverts
Chi Squared
Probability
event would
occur by chance
alone
1
17
15
.03
.65
2
20
12
1.53
.21
3
21
11
2.53
.11
4
22
10
3.78
.049
5
30
2
22.78
.001
Note that difference between rows 3 and 4. Untutored we would likely take each as
acceptable evidence of a connection. But in fact only 4 and 5 meet the standard of statistical
significance.
The difference in Row 2 is 8, but a difference of 8 or less would be
obtained by chance fully 21 percent of the time in such an
experiment.
— Hines, 216
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Interpreting statistically significant results
• A statistically significant result confirms the working hypothesis, yes? No!
• Demonstrating that the 22/10 result is statistically significant shows only that the result
was not likely due to chance, but rather to some non-chance factor.
• It does not yet follow that the non-chance factor is astrological influence.
• One must then show that there are no confounding factors—that is, factors other than
those mentioned in the working hypothesis that may account for the result.
• We advertised for our study subjects after all!
Law of Large Numbers
• Getting a statistically significant result means, recall, that if we conducted the
experiment 100 times, we should expect to get the 22/10 result 5 times as a result of
chance alone.
• That is rare, only 5% of the time. But given enough opportunities, rare things do occur—
in fact, we would expect them to.
Astrology and the Stats
• Statistical Analyses of astrological affects have been conducted. After reviewing the
literature, Dean (1977) concluded there is no evidence of any statistically significant
correlation between one’s sign and one’s personality.
◦ Forlano & Erhlich (1941) sampled 7,527 subjects and found no effect between sun
signs and extroversion.
◦ Lim (1975) sampled 163 subjects and found no correlation between sun signs and
extroversion.
Mayo, White and Eysenk
• Mayo, White and Eysenck (1975) sampled 2,324 subjects and found “impressive support”
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for a correlation.
◦ Later research showed the effect was an experimental artifact as the subjects had
prior knowledge of the personality traits supposedly associated with the signs.
◦ Later research Eysenck and Nias (1982) sampled 1,160 children (presumably
unaware of astrology) and found no correlation.
◦ Another study tested whether persons with such prior knowledge would show a
higher correlation than those who did not. 122 subjects were divided into 3 groups
(had knowledge, borderline knowledge, no knowledge). The latter two groups
showed no correlation between sun sign and extroversion. However, “the
knowledgeable group…showed a marked tendency to assess themselves in
accordance with astrological predictions.” (Hines 219)
◦ Research by Delaney and Woodward (1974) confirmed these results.
Moon Signs
• Moon signs are no better correlated.
• Nor are other traits—e.g., marital compatibility. Several studies have shown no affect of
sun sign on marriage or divorce (Dean 1977, Culver an Ianna 1984).
• See description of Carlson’s 1985 study in Hines 221-222
• For further discussion of the astrological research, see Schick and Vaughn pages 88-96
Magical thinking once more
• In the face of the compelling statistical evidence, one ought to conclude that there is no
basis whatsoever for astrology.
• Continued belief in astrology in the face of this evidence—though it may be the default
product of our belief engines—is nonetheless unfounded.
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Pseudoscience and Explanation
• Astrology founders on two grounds:
◦ Its causal explanation of the associations astrologist’s claim to discover between
signs and personality traits are logically and theoretically suspect.
◦ Moreover, the very correlations for which these causal explanations are offered do
not even exist.
• In the end, the “explanations” offered by astrologers are bad explanations.
• Hines has offered some insight into why.
• Our task: to carry this on.
Bibliography
Magical
Thinking.
(2017,
January
3).
Skeptic’s
Dictionary.
Retrieved
http://www.skepdic.com/magicalthinking
Alcock, J. The Belief Engine. Retrieved from http://www.csicop.org/si/show/belief_engine
Hines, T. (2003). Pseudoscience and the Paranormal. Prometheus Books.
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from