ENVR E-160
Spring 2015
Critical Thinking on Issues of
Environmental and Public Health
ENVR E-160
Tuesday 5:30 – 7:30 (U.S. East Coast time)
(course website under construction)
“If you would be a real seeker after truth, it is necessary that at least once in your life you
doubt, as far as possible, all things.”
René Descartes
Instructor:
David Ropeik
978 369-5675
cell 617 291-5266
[email protected]
What this course is about:
You will learn about environmental issues in this and other courses. But in this one, you
will also learn how to think about those issues more carefully, more objectively, more
analytically, a critical skill for environmental professionals or anyone who wants to make more
informed and healthier choices for themselves or their families.
We don’t think about things very rigorously. We like to think we do, but research into
how our mind works has found that we reach conclusions based on subconscious mental
shortcuts and emotional and instinctive cues rather than from careful conscious fact-based
reasoning. This is particularly true of many environmental issues. As a result, our views may feel
right, but sometimes they don’t match the evidence. That can create problems for us as
individuals, and for society.
This course is about how to understand and fight back against the built-in subconscious
obstacles that impair more careful critical thinking. We’ll tackle the challenge in a fun and
intellectually engaging way. Basically, you will be asked to approach issues as if you are a
reporter, thinking about environmental and public health issues not to see how you feel about
them yourself, but on behalf of a public looking to you for objectivity and ‘the truth’.
Imagine you are an environmental reporter working on a story about, say, pesticides or
nuclear power or genetically modified food. Despite what you already think and believe
personally, as a journalist you have to keep an open mind. You can’t let your biases and emotions
get in the way of objectively considering all the facts. You have to thoroughly seek out and fairly
consider all perspectives. You have to apply a healthy skepticism to challenge the information
you gather, and question the motivation of your sources to judge whether the information is
reliable. You have to be curious and dig for more information and ask “the next question”. You
can’t just take the first easy explanation or description of things, or the one that feels right based
on your values. You can’t decide what information to go after, and what information to include in
your story, based only on what feels right.
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Spring 2015
These general rules that guide a journalist’s approach to gathering and reporting
information are also good guidelines for anyone who wants to become honestly informed on any
issue, particularly on emotionally loaded environmental issues. Yet most of us usually don’t
follow these guidelines for our own critical thinking, so our opinions and views, and the choices
that result, are not as informed as they might be. They are based more on emotion that objective
analytical reason. That, in turn, can lead to dangerous personal behaviors, and public policies that
may feel right but don’t maximize public and environmental health.
This course will try to help you learn how to think about environmental and health issues
more rigorously, so your views and perspectives will be better informed. If you are in or planning
to enter any environmental profession, this course is immensely valuable. If you are just
interested in environmental and public health issues, this course will help you make choices will
be healthier for you and your family. You will learn about many issues along the way. But more
than that, you’ll learn how to think about them more carefully.
General Comments on Grading
Most of your grade will come from the papers you will have to write. The assignments
are supposed to be intellectually stimulating (fun, even), a chance to express your thoughts and
sometimes your opinions on several interesting topics. The papers are short. You don’t have to
be a great writer. I don’t grade based on your ability to write, but on your ability to think.
A friendly word of caution; you must meet the basic objectives of the assignment as
described in the syllabus and in class. If you don’t clearly understand those objectives, it is
your responsibility to clarify things before submitting your work. We will discuss each upcoming
assignment at the end of the class one week before it’s due. You can reach me online for
additional clarification.
Meeting The Technical Requirements To Allow Full Class Participation
In addition to the papers, 10% of your grade will be based on participation in our class
meetings, being there and engaging in the conversation with your fellow students from around
the world! This isn’t like a MOOC online course, where the M O stand for MASSIVE OPEN.
Enrolment in our course is limited.
Please pay close attention to the technical requirements for online students. We will be
using the ZOOM platform, which will allow us to see and hear each other in real time. It will be a
fully live virtual classroom experience. It’s important that you be aware of the specific technical
requirements to allow participation, like which computer operating systems work, microphones,
web
cams,
internet
connection
speed,
etc.
They
are
described
here
https://support.zoom.us/hc/en-us/articles/201362023-System-Requirements-for-PC-and-Mac .
In addition, when you enroll the Extension School will provide all the instructions you need to
participate.
PLEASE MAKE SURE YOU CAN MEET THESE REQUIREMENTS.
Being there and engaging in the conversation in real time IS EXPECTED. There are
two reasons for this. First, the discussions are fun. Many students in the past have said they
really look forward to the class meetings, just for the discussions. But more importantly,
participating in the discussion is a big part of how will you will learn. You will be challenged in
those discussions to think carefully. Class participation is essential practice for the critical
thinking this course is all about. You won’t be graded on how much you actually say (some
people tend to talk too much, some talk too little), but in-class discussion, including your active
input, is a great exercise for sharpening your critical thinking. So you have to attend at least 12
of our 15 meetings. Attendance will be recorded.
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I’m pretty flexible if you have to miss class. You just have to let me know in advance.
Grading for Undergraduates:
Attendance and class participation (see notes above) = 10%
Papers: This is the most important way you will demonstrate critical thinking. You will
be expected to demonstrate progress in your critical thinking skills through these
assignments as the course progresses. That means that however carefully you
have thought about things in your early papers, I’ll be looking for even more
critical thinking in the later assignments. The standard for getting a good
grade gets higher with each paper! That is, each successive assignment has
to demonstrate better and more careful critical thinking.
#1
#2
#3
#4
#5
Risk perception = 10%
News coverage of risk = 15% of grade
Cost-Benefit Analysis = 15% of grade
Midterm paper on Precautionary Principle =20% of grade
Final papers = 30% of grade
Grading for Graduate Students:
Attendance and class participation = 10%
Papers
#1
#2
#3
#4
#5
#6
Risk perception = 5%
News coverage of risk = 10% of grade
Midterm paper on Precautionary Principle = 15% of gradE
Cost-Benefit Analysis = 15% of grade
Silent Spring as advocacy – 10% of grade
Final papers = 35% of grade
A few words about writing style:
There is a decent amount of writing for this course. The good news is, the papers are
short. The bad news is, it’s hard to concisely say all you want to say in just a couple pages. This
imposed brevity will force you to think carefully about the core of what you want to say. So be
clear. Be direct. Don’t worry about being fancy or erudite. You will not be graded on your
writing style. These papers need to demonstrate that you are thinking about the topic carefully,
thoroughly. You can write your papers in any style you like, but I prefer a conversational style
rather than a more formal academic style.
A few thoughts about attribution. You need to cite the source for any fact not understood
to be common knowledge. (The earth is round? No citation necessary. The average temperature
of the climate is warming at such and such a rate….according to who? I suggest you cite your
sources directly in the copy, with quotations and a full identification of the source. For example;
“Global warming is a bunch of hooey” according to climatologist William
Everythingiswonderful, Professor of Earth Science at So and So U., who has studied the issue for
15 years.”. Or you can use the journalistic style of paraphrasing what your source says and citing
who they are; For example; Recent findings suggest climate change may be causing the worst
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Spring 2015
mass extinction of life on earth in the history of the planet, according to biologist Susan
Theskyisfalling, a member of the Intergovernmental Panel on Climate Change.
If you choose, you can use academic notation to acknowledge your sources. If you do,
please include the notation in parentheses right after the fact you are attributing, rather than
with footnotes or endnotes. Here’s an example; “Global warming is expected to raise ocean levels
by as much as 7 feet by 2050. (IPCC Summary Report, 2001).” If you are citing something you
found online, you must include the link to that source.
Finally, please submit your papers electronically to [email protected]. Format them at
1.5 lines (between single and double spaced).
Deadlines:
As would be the case for any work assignment for a reporter in the real world, you have
to meet your deadline, and the deadline for submitting your homework is the beginning of the
class when it’s due. If you miss that deadline, and you haven’t gotten an extension (I can be
pretty flexible about that, as long as it’s worked out in advance), the work fails .
COURSE SCHEDULE
SESSION 1, JANUARY 26 – OVERVIEW. RISK RANKING EXERCISE. NUCLEAR
POWER AS AN EXAMPLE OF THE CHALLENGE OF CRITICAL THINKING.
 Introduction of Instructor.
 Purpose of class. Review of syllabus. Students introduce themselves.
 A risk ranking exercise using a list of environmental and public health issues. Discussion
of where those beliefs come from.
 Presentation on and discussion of the issue of nuclear power to test beliefs, and the
knowledge on which those beliefs are based.
ASSIGNMENTS:
 Read “On Reason and Emotion”, posted on course website

Begin reading Kahneman, “Thinking Fast and Slow”. It’s fascinating and
important, and we’ll be talking about it in class in Session 4 on February 16.
It’s the kind of book you have to read and think about, so it can be slower
going than, say, an adventure novel. Get started now.)
SESSION 2, FEBRUARY 2 - COGNITIVE CHALLENGES TO CRITICAL THINKING.
THE CAUSES OF THE RISK PERCEPTION GAP, PART 1.
Most of the environmental and public health issues we’ll be talking about involve
some degree of risk, the possibility of harm. This session will begin a three lecture series
on the neurobiology, psychology, and sociology of the subjective way humans perceive
risk. We’ll learn about “The Risk Perception Gap” between our fears and the facts, the
dangers that arise when we are more afraid of things than we need to be, or less afraid of
them than we should be. We will consider examples of the risks we face when we fail to
think critically about environmental and public health issues.
ASSIGNMENT:
Critical Thinking on Issues of Environmental and Public Health / David P. Ropeik, Instructor / Page 4 of 11
ENVR E-160

Spring 2015
Read “Be Afraid of Being Very Afraid”, posted on course website
SESSION 3, FEBRUARY 9 - COGNITIVE CHALLENGES TO CRITICAL THINKING.
THE CAUSES OF THE RISK PERCEPTION GAP, PART 2.
More on the psychological, social, and cultural influences on our perception of
risk.
ASSIGNMENT:
 Write a 2 page paper describing one example of how specific cognitive risk
perception factors discussed in class over the previous two weeks led to a Risk
Perception Gap in yourself, a friend or family member, or in society. Identify
which specific perception factors contributed to the gap, and how those factors
made the fear greater, or smaller, than the facts of the risk suggested would be
appropriate. Due no later than next class, February 16
SESSION 4, FEBRUARY 16 – COGNITIVE CHALLENGES TO CRITICAL THINKING.
THE CAUSES OF THE RISK PERCEPTION GAP, PART 3.
The satirist Ambrose Bierce observed (paraphrasing) that the brain is “the organ
with which we think we think”. In fact, a vast amount of what goes into the judgments and
decisions we make happens well below the radar screen of conscious purposeful thought. Beyond
the specific elements that contribute to our perceptions of risk issues, we’ll dive into the
fascinating world of how we really ‘think’, and discover the hidden forces that shape our
perceptions more generally and contribute to thinking that often leads to choices and judgments
that seem to conflict with ‘rationality’. This is where we’ll talk about ‘Thinking, Fast and Slow”.
ASSIGNMENTS:
 To prepare for next week’s discussion, read three news articles on Mad Cow
disease, posted on course website
Scientific Data Offer No Proof of Beef Safety (a Wall Street Journal article reprinted at
http://www.mindfully.org/Food/2003/Mad-Cow-No-Safety29dec03.htm
Scientists Weigh Risks of Beef; Muscle Alone Found Unlikely to Carry Mad Cow Disease
http://www.google.com/http%3A%2F%2Fisites.harvard.edu%2Ffs%2Fdocs%2Ficb.topic
743335.files%2Fbrown%20washpost%20on%20mad%20cow.doc
Media Stampede (again) on mad cow coverage
http://articles.latimes.com/2004/jan/11/entertainment/ca-shaw11

Begin reading Chapters 1-5 “Risk and Reason”, Cass Sunstein. We’ll talk about
these issues in two weeks, on March 1, but there is a fair amount of reading, so
start now.
SESSION 5, FEBRUARY 23 - NEWS COVERAGE OF RISK
How the news media cover risk. We will examine the ways in which the news
media often play up the negative, controversial, or frightening aspects of risk stories. We
will explore the motivations of journalists, including the role of risk perception in news
Critical Thinking on Issues of Environmental and Public Health / David P. Ropeik, Instructor / Page 5 of 11
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Spring 2015
decision making. We will hopefully be joined by a journalist to discuss how the media
report on public health and environmental issues.
ASSIGNMENTS:
 Find an example of press coverage of a public health or environmental risk issue.
Write a 2 page critique of the coverage. This is not a regurgitation of what the
story said, but a critical ANALYSIS, A CRITIQ
UE, commenting on whether
the report was good, bad, fair, balanced, inflammatory. Tell me WHY! Did it play
up the scary and play down the neutral, or get it about right? (INCLUDE THE
COVERAGE YOU ARE CRITIQUING WITH YOUR ASSIGNMENT,
EITHER AS A PHYSICAL COPY OR A LINK.) Due no later than class next
week, March 1.

Finish reading Chapters 1-5 of “Risk and Reason”. We’ll talk about it in class next
week, and then there is a paper due on it when we return from Spring Break,
March 22. That’s a reasonable amount of time, but there is other reading to do
over the break…so get your reading of “Risk and Reason” done now!
SESSION 6, MARCH 1 – RISK ANALYSIS. A COMPREHENSIVE WAY OF
UNDERSTANDING RISK AND MAKING POLICY CHOICES.
How do policy makers and regulators think carefully and rationally about
environmental issues as they try to identify strategies that will maximize human and
environmental health with the most efficient use of limited financial resources. One main
approach is Cost-Benefit Analysis, the process described in Risk and Reason, the book
you’ve been reading. It helps determine whether the costs to implement a policy are
greater or less than its health benefits. The trouble is, that requires putting a monetary
value on human life so we can compare the health benefits of a policy to its costs in
monetary terms.
The process of risk analysis, Cost-Benefit Analysis, and in particular the way
that a dollar value is placed on human health benefits, will be explained by Joshua Cohen,
who has done influential risk analyses of issues from Mad Cow disease to cell phones and
driving to mercury in fish. He will discuss his work, how risk assessors value human life,
and the value of a quantitative risk analytic approach to critical thinking about
environmental and public health issues.
ASSIGNMENTS:
 Write a 3-4 pp paper taking a position on the use of Cost Benefit Analysis; Are
you for it? Against it? If it should be used, in what ways, or under what
circumstances? Why? You can refer to Sunstein, but this is NOT a book review
of Risk and Reason. The assignment is to take a position on Cost Benefit
Analysis and argue thoughtfully for it. Due no later than class when we return
after the break, March 22, so you have three weeks for this.

To prepare for the next class, March 8, read the papers and watch the videos on
the Precautionary Principle posted on the course website, and anything else on the
issue you want to read on the topic of the Precautionary Principle. It’s the topic of
your midterm paper.)
Critical Thinking on Issues of Environmental and Public Health / David P. Ropeik, Instructor / Page 6 of 11
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Spring 2015
SESSION 7, MARCH 8 - THE PRECAUTIONARY PRINCIPLE
Risk management policy makers and regulators struggle with what to do about
risks when all the facts aren’t in. Should we ban substances or processes that may be
dangerous before we know what they might do to us or the environment? Or does
banning them before we know whether they may actually poise a danger deny us the
benefits of those products or processes? How sure do we need to be before allowing a
potential risk genie out of the bottle? We all know the phrase “Better Safe Than Sorry”.
In legal and economic arenas, this is known as The Precautionary Principle (PP), an
attempt to embed “Better Safe Than Sorry” into law.
ASSIGNMENT:
 A paper taking a position on the Precautionary Principle. For it? Against it? In
what form? Why? Careful argumentation requires you to foresee and counter any
arguments that could be made against your position. 5 pages maximum for
undergraduates, 10 pages maximum for graduate students. You have three
weeks to work on this. Due in by class on March 29.
(no class on Monday 3/15, Spring Break. HAVE FUN!)
SESSION 8, MARCH 22 – THERE’S MORE TO “RISK” THAN MEETS THE EYE. THE
FACTUAL ELEMENTS THAT INFORM TECHNICAL RISK ASSESSMENT.
After considering in the first few classes what makes something feel like a risk, now we’ll
get into the science of what makes something actually dangerous. We’ll break down the
concept of risk into its component parts, Hazard and Exposure, and consider the details
that governments use when they do the risk assessments on which safety standards are
based.
ASSIGNMENTS:
 Read Introduction and any three chapters of “RISK!!!”

Read “How Risky Is Flying?”
http://www.pbs.org/wgbh/nova/planecrash/risky.html

Start Reading Silent Spring. We’ll be discussing it in two weeks on April 5, and
graduate students have to write a paper about it.
SESSION 9, MARCH 29 – WHERE DO “THE FACTS” COME FROM? – 1,
TOXICOLOGY, WHAT IT CAN TELL US, WHAT IT CAN’T.
Toxicology is the study of poisons. It is the science that regulators depend on
to think critically about environmental and health risks in order to determine,
objectively, what levels of exposure, to which substances, are safe. But toxicology is
fraught with limitations. Testing animals, or just testing cells, is not the same as testing
humans. We will learn the basics of how chemical testing is done, and what those tests
can tell us, and what they can’t.
ASSIGNMENTS:
 Finish reading “Silent Spring”
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Spring 2015
Read
“Chemicals,
Regulation,
and
Real
Science”
at
http://www.ethicalcorp.com/communications-reporting/chemicals-regulationand-real-science-troubling-case-bpa
SESSION 10, APRIL 5 – ADVOCACY – THE POWER OF SPIN.
We will discuss Silent Spring and Chemicals, Regulation, and Real Science. We will
also hear a presentation about a current issue from an advocate of one side of that issue,
and discuss the issue with that advocate and challenge him or her with critical, skeptical
thinking.
ASSIGNMENTS FOR GRADUATE STUDENTS:
 Write a 2-3 page paper commenting on “Silent Spring”, commenting whether it is
advocacy, reliable unbiased fact, or both. Due no later than class next week, April
12
FOR ALL STUDENTS
To prepare for class next week, read parts one and two of the story of John Snow,
“The
Father
of
Modern
Epidemiology”,
at
http://www.ph.ucla.edu/epi/snow/fatherofepidemiology.html#
and
http://www.ph.ucla.edu/epi/snow/fatherofepidemiology_part2.html#

Graduate students; By next week you have to let me know what topic you want to
debate in one of the three final classes on April 26, May 3, or May 10. Please read
the description of that debate below in Sessions 13, 14, and 15. Read the
description and choose a topic (I will also circulate some suggestions from which
you can choose), and get it to me by April 12. This is just for my review and
approval of the topic. No real detail on the debate issue is necessary at this time.
SESSION 11, APRIL 12 –
WHERE DO “THE FACTS” COME FROM? – 2,
EPIDEMIOLOGY, WHAT IT CAN TELL US, WHAT IT CAN’T
Epidemiology is the study of patterns of health in groups of people to try and
discern what might be causing health problems. Like toxicology, it is an important tool
for regulators as they to make informed, objective, evidence-based public health policy.
But like toxicology, epidemiology also faces many limitations. We will hear from an
expert in the field about what epidemiology is, how it is done, and what epidemiology can
and can’t say about threats to our health.
SESSION 12, APRIL 19 - PUBLIC HEALTH – THE LACK OF CRITICAL THINKING
ABOUT THE BIG THREATS.
Heart Disease. Motor Vehicle crashes. Flu. Food poisoning. The big risks often
don’t evoke the same degree of concern. We will discuss why that is so, the role of public
health agencies in keeping us safe and healthy, and how our lack of concern about these
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major issues results in underfunding of those critical agencies, leaving us at greater risk!
(OOPS!)
ASSIGNMENTS:

Graduate students; By next week you have to let me know what risk topic you want to
write about in your final paper writing a short book chapter in the form of a chapter from
“Risk!!!”. This is one of your three final papers, described in the syllabus under
ASSIGNMENT after Session 13, April 26. Read that description and let me know what
topic you’d like to write about. No real detail on the issue is necessary at this time. You
may want to write about the same topic you have chosen to debate in the final class
sessions. That’s okay, subject to my approval.
ASSIGNMENT:
 All students; Submit your proposed topics for your final assignment papers,
arguing the same issue pro and con. THESE TOPICS MUST RECEIVE PRIOR
APPROVAL. Due not later than April 26.
SESSION 13, APRIL 26 (and MAY 3, MAY 10) CLASS DEBATES ON RISK ISSUES BY
GRADUATE STUDENTS
Graduate students will debate risk-related topics, chosen jointly by me and the
students in advance (see ASSIGNMENTS after Session 10, April 5, requiring topics to be
submitted for prior approval.) These debates are intended to educate the class about the
topic, to challenge the presenters to think about the topic carefully and thoroughly, and to
challenge the rest of the class to think critically about the presentation and engage in
active skeptical discussion with the presenters.
Graduate students:
You will present one side of the issue, and another student will present the
opposite side of that topic. Each student will have 25 minutes, uninterrupted by any
questions, to present their case. Then each side will have 10 minutes to rebut and
challenge the other side’s case, and the final 50 minutes will be for open questioning from
the rest of the class. At the end, we’ll vote on which side seemed more persuasive.
You can use any kind of presentation materials you want, or none at all.
I will be a stern timekeeper. A 25 minute presentation can actually go by pretty
fast, and a 10 minute rebuttal even faster, so bear that in mind as you prepare.
You are required to choose a topic you DON’T KNOW MUCH ABOUT! To
choose topics, email me your preferences no later than April 12. I'll let you know
what you'll be doing shortly thereafter.
This will NOT be a part of your grade. Nor will it supplant the third paper you
have to write as part of your final assignment, “A book chapter in the form of a chapter
from RISK!, written to educate the general public in a comprehensive, neutral, reliable
way on an issue you know little about.” What you can do, if you choose, is write your final
paper on the same risk issue you’re talking about in the debate. Remember, the final
assignment is to be a neutral informative factual article, whereas the debate will require
you to take one side or the other. Or you can choose a different topic for your final paper,
Critical Thinking on Issues of Environmental and Public Health / David P. Ropeik, Instructor / Page 9 of 11
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the one written like a chapter in the book RISK!!!, in which case you need to clear the
topic with me no later than class 4/19, as specified in the syllabus.
The idea of this exercise is to challenge you to think about an issue carefully. Given
that you are trying to be the most persuasive arguer, and that the other side is going to
rebut your case, and given that your fellow students and I will ask you skeptical
challenging questions about your position, this should be a healthy exercise to challenge
your critical thinking. I think this will fun for you, and engaging for the class.
ASSIGNMENTS:
 FINAL PAPERS – Due by our last class, May 10
1. A paper, 4 pages maximum, on a controversial risk issue of your choice (the topic must
be pre-approved by the Instructor…see ASSIGNMENT after Session 12, April 19),
arguing in favor of the position you are comfortable with.
2. A paper, 4 pages maximum, describing the same risk issue, arguing the opposite
position.
I am not supposed to be able to tell which side of this issue you are on! You
need to argue both sides equally well and persuasively.
3. GRADUATE STUDENTS ONLY: A book chapter in the form of a chapter from
“Risk!!!”, (the information in your chapter has to be organized under similar subheadings)
written in a way that would educate the general public in a comprehensive, neutral,
objective way on an issue you know little about. AS WITH YOUR DEBATE TOPICS,
THE TOPIC FOR THESE CHAPTERS MUST BE PRE-APPROVED BY ME. SEE
ASSIGNMENT AFTER SESSION
SESSION 14, MAY 3 – Graduate Student Issue debates
SESSION 15, 5/10 - Graduate Student Issue debates
READING
Books to buy, available through the Harvard COOP:
RISK!!!! - Ropeik and Gray
Risk and Reason – Sunstein
Silent Spring – Carson
Thinking Fast and Slow - Kahneman
Readings available at the Harvard Extension School Library :
The Emotional Brain, Ledoux. On the neuroscience of emotion.
Judgment and Uncertainty, Biases and Heuristics, Kahneman, Tversky,
Slovic. A classic about the roots of “irrational” decision making.
Risk Perception, Slovic. The seminal papers in the field of risk perception
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Psychology.
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