The Nocebo Effect
HW3
Not Fallacies
The following things are not fallacies:
• Having traditions
• Being popular
• Lacking evidence
Appeal to Tradition
Some people have the “traditional” belief that
keeping a pet turtle slows down your business
and ruins your fortune.
There are lots of reasons they might have for
this: belief in sympathetic magic, confirmation
bias, hearsay, etc. None of these are good
reasons.
Appeal to Tradition
But just because someone has a traditional
belief that is false and held for bad reasons does
not mean they’ve committed the ‘appeal to
tradition’ fallacy.
The fallacy only happens when someone
presents the fact that this is a traditional belief
as a reason to believe it.
Appeal to Tradition
“Marriage has traditionally been between a man
and a woman, therefore, gay marriage should
not be allowed.”
Appeal to Popularity
Many things are popular and widely believed.
Some of them are false – like the belief that
aliens visited ancient humans on Earth.
This does not mean that the ‘appeal to
popularity’ fallacy has been committed!
Bad Reasons
Bad reasons to believe in aliens:
• Erich von Daniken told you to.
• That gold thingy sort of looks like a spaceship.
• Ancient Indian texts talk about flying chariots
called ‘vimanas.’
• No one could build the pyramids without the
help of alien technology.
• It’s possible for aliens to come and visit.
Appeal to Popularity
If those are the reasons you believe aliens came
to Earth, then you are not committing the
appeal to popularity fallacy – even if your belief
is a popular one!
To commit the fallacy, you have to argue that
the reason to believe in aliens is that lots of
other people believe in aliens.
Appeal to Popularity
“In history, Buddhists talk about karma.
Christians talk about deeds. Taoists talk about
te. Other spiritual beings talk about virtue.
These are different words for the same thing.
Millions of people believe in karma. Millions of
people desperately want to clear their own
karma.” -- The Power of Soul, Zhi Gang Sha
(Also note equivocation)
Appeal to Popularity
After Fukushima, many
people in China and
California rushed out to
buy salt.
Why? Some people may
have had some dumb
scientific idea, but for
most it was because that’s
what everyone else was
doing.
No Reasons
Sometimes people believe things that there is
no evidence to support.
This might be bad, but it’s not a fallacy.
A fallacy is a misleading form of argument. But
having no argument is not the same as having a
misleading one!
N
How many people do you have to survey to find
out what everyone believes? If there are 7
million Hong Kongers, do you have to ask 7
million people?
NO:
http://help.surveymonkey.com/articles/en_US/k
b/How-many-respondents-do-I-need
N
Let’s imagine that the HK population is 10
million.
Then, according to the chart, if we ask 400
(randomly selected) people what they think, and
82% of them say “X,” then we know that
between 77% and 87% of all 10 million say “X.”
Survey Methodology
Do NOT, EVER, tell me that “they only looked at
1,000 people, how can this reflect what 7 million
Hong Kongers think.” NEVER.
If you don’t understand the math, that’s fine.
But good survey methodology is good, and
shouldn’t be doubted out of ignorance.
Straw Man Fallacy
Many in Hong Kong think
that President Benigno
Aquino of the Philippines
should apologize for the
Manila bus crisis.
Straw Man
Aquino argues:
1. No one should apologize for something that
they did not do.
2. Rolando Mendoza acted alone in taking
hostages and in killing hostages. The
Philippine government didn’t do it and the
Philippine people didn’t do it.
3. Therefore, the government/ people of the
Philippines should not apologize.
Straw Man Fallacy
A straw man argument is where you
mischaracterize your opponent’s claims or
reasons for those claims. You show that the
mischaracterization is false or misleading, and
then claim that your opponent believes false
claims or has bad reasons for her claims.
Straw Man Fallacy
Aquino is suggesting that people want him to
apologize for Mendoza’s actions.
BUT that is not what people want. They want
him to apologize for the Philippine government’s
actions: specifically, the way the crisis was
mishandled by the police.
Distribution Fallacy
The distribution fallacy is when you assume that
the parts have the same properties as the whole
they comprise:
1. Lingnan has a great philosophy department.
2. Therefore, Michael is a great philosopher.
1. For the “whole” of Hong Kong kindergartens,
there is enough space for all children to go to
school.
2. Demand is for 168,000 spaces, but there are
a total of 241,000 spaces.
3. Therefore, there is no shortage of space in
kindergartens.
Distribution Fallacy
Just because there is enough space in the whole
system does not mean there is enough space in
the high-demand districts.
Mainlanders want to go to kindergarten in the
northern districts, because that’s closer to
China. These kindergarten seats have much
lower availability.
False Dilemma
The false dilemma fallacy
is when someone presents
two options as the only
possible options, when in
fact there are other
options.
False Dilemma
“Every nation has to either
be with us, or against us.
Those who harbor
terrorists, or who finance
them, are going to pay a
price.” – Hilary Clinton
False Dilemma
“Either you are with us, or
you are with the
terrorists.” – George W.
Bush
National Education
1. We can either have
national education
with the materials we
now have, or not have
national education.
2. The materials now
falsely portray China
and ignore historical
events like Tiananmen
Square.
National Education
3. Therefore, there should
be no national education
in Hong Kong.
HW4
“Bacon Lowers Sperm Count”
“Researchers found that
men who regularly ate
processed meat had
significantly lower
amounts of normal sperm,
compared with those who
limited the amount of
foods like bacon,
sausages, hamburgers,
ham and mince.”
Correlated Variables
A1 = Eating processed meat.
B1 = Low semen quality (sperm count, size,
shape).
A2 = Eating fish.
B2 = High semen quality.
A causes B?
Processed meat lower sperm count because it
makes you fat:
“male obesity impacts negatively on male
reproductive potential not only reducing sperm
quality, but in particular altering the physical
and molecular structure of germ cells in the
testes and ultimately mature sperm.”
A causes B?
Processed Meat → Fat → Low Sperm Quality
Common Cause?
Testosterone is a hormone that influences
sperm development. Eating meat increases
testosterone. Maybe if you lack testosterone,
your body wants meat to get more of it.
Common Cause
Eating Meat to Replace Testosterone
↑
Low Testosterone
↓
Low Sperm Count
Extra Problem!
“The study by Harvard University on 156 men in
couples suffering problems conceiving examined
their diet and the size and shape of their
sperm.”
Stroke and Airports
“A study published online by the British Medical
Journal looking at the health of people living in
the vicinity of Heathrow airport found those
with the highest exposure were 10-20% more
likely to be admitted to hospital for stroke,
coronary heart disease and cardiovascular
disease. There was also an increased risk of
death from those diseases.”
Correlations
A = Living near an airport.
B = Having/ Dying from
heart disease.
Controlling For
The researchers controlled for socioeconomic
status and ethnicity.
This means that among poor people, those who
lived near the airport were more likely to have
heart disease. And among rich people it was the
same. White people near the airport had more
heart disease; black people did too.
A causes B?
The noise of living near
the airport “rais[es]blood
pressure or… disturb[s]
people's sleep.” Higher
blood pressure and lack of
sleep then cause heart
problems.
A causes B?
Loud Noise
↓
High Blood Pressure
↓
Heart Disease
Common Cause
Stressful job: people who live near airports are
more likely to work at airports, and fly a lot.
Living Near an Airport
↑
Working at an Airport
↓
Stress, Heart Disease
Correlation
“[A]mong first-year
students, those who sent
the most text messages
had the poorest sleep
habits and lowest levels of
emotional well-being.”
A causes B
A = texting
B = sleeping poorly/ feeling bad
“If you’re texting a lot, that’s actually work. It
takes time,” Murdock said. “If you’re feeling
overloaded and also texting a lot, the texting
might be adding to your burden.”
Common Cause?
Maybe texting doesn’t add to your life burden.
Maybe you text because your life is difficult. For
example, you might have a long conversation
with a girlfriend/ boyfriend/ parent/ sibling
during difficult times, but a short one during
normal times.
Common Cause?
Texting a lot with friends/ family/ partners
↑
Difficult time in your life
↓
Feeling stressed, not sleeping
THE NOCEBO EFFECT
If it works, it doesn’t matter how
A common defense of “placebo medicine”
(medicine that was no better than a placebo) is
that it didn’t matter whether the treatment
caused the improvement or our beliefs about
the treatment caused the improvement—
The improvement is all that matters!
The Nocebo Effect
‘Placebo’ is Latin for “I will please,” and the
placebo effect is when a treatment that doesn’t
by itself cause any improvement leads to
positive expectations in the patient that cause
improvement.
‘Nocebo’ means “I will harm,” and the nocebo
effect is when an inactive treatment causes
harm, because we believe that it will.
Basic Tastes
In the early 20th Century, Western scientists
thought that there were 4 basic tastes:
•
•
•
•
Sweet: peach, strawberry, honey
Sour: lemon, grape, tamarind, kimchi
Salty: salt
Bitter: lime, chocolate, coffee, dark greens
Spicy!
Asian scientists actually
recognized another taste:
spicy!
Umami
In 1908 Kikunae Ikeda proposed another basic
taste: umami (savory, meaty). He isolated the
chemical that caused it (glutamate) and found a
way to powerfully increase the flavor (MSG).
Umami: Cheese, soy sauce, tomatoes, beans,
mushrooms, seaweed.
“Chinese Restaurant Syndrome”
In 1986, Dr. Robert Ho Man Kwok wrote a letter
to the New England Journal of Medicine,
describing the symptoms he seemed to
experience after eating Northern Chinese food
in America: “numbness at the back of the neck,
gradually radiating to both arms and the back,
general weakness and palpitation.” He
speculated that MSG was the cause.
CRS and MSG
In 1987, an article was published in the
prestigious journal Science blaming MSG.
Since then, a large number of Americans have
come to believe that they are allergic to MSG
and experience CRS.
Even in Hong Kong, I see restaurants all the time
that advertise “No MSG!”
Silliness
But this is ridiculous!
1. MSG is delicious.
2. Glutamate is in everything with an umami
flavor. There’s lots of it in tomatoes.
3. All the science says that CRS is a nocebo
effect.
And the Science Says…
In fact, in multiple double-blind placebocontrolled trials conducted by Geha et. al.
(2000), where all the participants believed they
were sensitive to/ allergic to MSG, it was found
that there was no difference in reaction
between the MSG group (experimental) and the
placebo control group. Other similar studies
have had similar results.
Why?
Where did this belief come from? Well, it
probably began with normal accidental
correlations, confirmation bias (only noticing the
times when you felt less than perfect after
eating Chinese) and “goalpost shifting”:
http://www.saynotomsg.com/basics_symptoms.
php lists 62 different symptoms of MSG. How
likely is it that you experience one by accident
every time you eat Chinese?
And Racism
You also can never rule out the fact that some
Americans are racially prejudiced against
Chinese. They perceive the food as alien and
different and thus judge it as wrong and
unhealthy, not suited for “civilized” people. (I’m
sure a lot of this is unconscious.)
More Nocebo
Recently, people have
started to report “Wind
Turbine Syndrome.”
People living near turbines
have complained of lost
sleep, headaches, nasuea,
memory loss, dizziness,
depression… an
astonishing 155 symptoms
in total!
Why?
First, this isn’t real. There are no noticeable
differences in health problems in communities
situated near wind farms, as all 17 studies of the
effects of wind farms on health have shown.
http://theconversation.edu.au/wind-turbinesyndrome-a-classic-communicated-disease-8318
Making People Sick for Money
But oil and gas companies (and the politicians
they’ve purchased) have an interest in
convincing people that alternative energy is bad
for them.
What began as someone misinterpreting the
cause of (probably real) symptoms, has become
a case of demagogues convincing people to be
sick for their own political aims.
The Point
Something is wrong with the argument “if it
works, it doesn’t matter how it works” for
placebos.
The same argument could be given for nocebos:
“if it hurts, it doesn’t matter how it hurts: so
stop using MSG, and get rid of those wind
farms!”