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In which John Green teaches you about the end of the Cold War and the presidency of George H.W. Bush. It was neither the best of times, nor the worst of times. On the domestic front, the first president Bush inherited the relative prosperity of the later Reagan years, and watched that prosperity evaporate. That was about all the interest Bush 41 had, domestically, so let's move to foreign policy, which was a bigger deal at this time. The biggie was the end of the Cold War, which is the title of the video, so you know it's important. The collapse of the Soviet Union was the biggest deal of Bush's term, and history has assigned the credit to Ronald Reagan. We give the guy a break, and say that he helped. He was certainly expert in foreign policy, having been and envoy to China, ambassador to the United Nations, and head of the CIA. Bush also oversaw the first Gulf War, which was something of a success, in that the primary mission was accomplished, and the vast majority of the troops were home in short order. It didn't do much to address some of the other problems in the region, but we'll get to that in the next few weeks. Along with all this, you'll learn about Bush's actions, or lack thereof, in Somalia and the Balkans, and you'll even be given an opportunity to read Bush's lips.

Thanks to Michael Williams at http://www.mylifeinplastic.com for the Barbies.

Crash Course World History is now available on DVD! Visit http://dft.ba/-CCWHDVD to buy a set for your home or classroom.

Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. During President H.W. Bush’s time in office, he oversaw the U.S. response to the fall of the Berlin Wall and end of the USSR: https://www.commonlit.org/texts/the-berlin-wall

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So, during times of inflation or deflation, why doesn't the government just set prices? It sounds reasonable, but price ceilings or floors just don't work. Adriene and Jacob explain why. Subsidies, however, are a little different, and sometimes they even work. We'll also explain that. Today you'll learn about stuff like price controls, deadweight loss, subsidies, and efficiency.

Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

Mark, Eric Kitchen, Jessica Wode, Jeffrey Thompson, Steve Marshall, Moritz Schmidt, Robert Kunz, Tim Curwick, Jason A Saslow, SR Foxley, Elliot Beter, Jacob Ash, Christian, Jan Schmid, Jirat, Christy Huddleston, Daniel Baulig, Chris Peters, Anna-Ester Volozh, Ian Dundore, Caleb Weeks

--

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Continuing our look at Nuclear Chemistry, Hank takes this episode to talk about Fusion and Fission. What they mean, how they work, their positives, negatives, and dangers. Plus, E=mc2, Mass Defect, and Applications of Fission and Fusion in the real world!

--
Table of Contents

E=mc2
Mass Defect
Fission vs. Fusion
Applications in the Real World

--
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In which John Green teaches you about the early days of the Civil Rights movement. By way of providing context for this, John also talks a bit about wider America in the 1950s. The 1950s are a deeply nostalgic period for many Americans, but there is more than a little idealizing going on here. The 1950s were a time of economic expansion, new technologies, and a growing middle class. America was becoming a suburban nation thanks to cookie-cutter housing developments like the Levittowns. While the white working class saw their wages and status improve, the proverbial rising tide wasn't lifting all proverbial ships. A lot of people were excluded from the prosperity of the 1950s. Segregation in housing and education made for some serious inequality for African Americans. As a result, the Civil Rights movement was born. John will talk about the early careers of Martin Luther King, Thurgood Marshall, Rosa Parks, and even Earl Warren. He'll teach you about Brown v Board of Education, and the lesser known Mendez vs Westminster, the Montgomery Bus Boycott, and all kinds of other stuff.

Crash Course World History is now available on DVD! Visit http://dft.ba/-CCWHDVD to buy a set for your home or classroom.

Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. The Civil Rights Movement gained national attention with the murder of Emmett Till in 1955: https://www.commonlit.org/texts/emmett-till
That same year, Rosa Parks refused to give up her seat on a Montgomery bus, beginning the Montgomery bus boycott: https://www.commonlit.org/text....s/rosa-parks-and-the
A young preacher named Martin Luther King Jr. gained national fame rallying support for the Montgomery bus boycott: https://www.commonlit.org/text....s/martin-luther-king
The end of segregation also began in the South with the Showdown in Little Rock in 1957: https://www.commonlit.org/text....s/showdown-in-little

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***
In our final episode of Crash Course Psychology, Hank discusses the ideas of Aggression and Altruism. These two things are difficult to understand and explain so sit tight and get ready to run the gauntlet of human emotions.

If you are currently in need of help: http://www.mentalhealth.gov/get-help/

--
Table of Contents:

Robber's Cave Experiment 0:00
Realistic Conflict Theory 0:57
Physical & Environmental Triggers 3:23
Frustration-Aggression Hypothesis 4:24
Altruism 5:25
Bystander Effect 5:56
Social Exchange Theory 7:19

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Hank takes us on a trip around the body - we follow the circulatory and respiratory systems as they deliver oxygen and remove carbon dioxide from cells, and help make it possible for our bodies to function.

Crash Course Biology is now available on DVD! http://dft.ba/-8bCC

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Table of Contents
1) Respiratory System 00:48
2) Simple Diffusion 00:55
3) Respiratory Anatomy 02:35
a) Trachea to Capillaries 03:10
4) Lung Function & Thoracic Diaphragm 04:37
5) Circulatory System 05:35
6) Circulatory Anatomy 05:54
a) Left Ventricle to Capillary Beds 06:50
b) Veins to Left Atrium 08:46
7) Endotherms & Ectotherms 09:20

References for this episode can be found in the Google document here: http://dft.ba/-3cHg

This video uses the following sounds from Freesound.org:
"00559 deep breathing 1.wav" by Robinhood76

crash course, crashcourse, biology, animals, oxygen, carbon dioxide, cellular respiration, circulatory system, respiratory system, circulation, respiration, heart, lung, artery, vein, pulmonary, simple diffusion, membrane, lungfish, larynx, trachea, bronchus, bronchiole, alveolus, capillary, blood, inhale, exhale, diaphragm, thoracic, pressure, breathing, breath, pump, red blood cell, four chambered heart, ventricle, muscle, aorta, vena cava, atrium, endotherm, ectotherm, hank green Support CrashCourse on Subbable: http://subbable.com/crashcourse

Today Phil explores the world of tides! What is the relationship between tides and gravity? How do planets and their moons become tidally locked? What would happen if you were 300km tall? Important questions.

--

Gravity Over Distance 0:44
Tidal Force Parameters 1:35
Battle of the Bulges 2:55
Tidal Lock 6:17

--

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--

PHOTO/VIDEO CREDITS
Photo & video credit: "NASA's Scientific Visualization Studio"
http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=4 Photo credit: "NASA's Scientific Visualization Studio"
https://www.flickr.com/photos/....gsfc/8556665115/in/p
http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1
The Hopewell Rocks - https://www.youtube.com/watch?v=EnDJ6_XpGfo

Want more videos about psychology every Monday and Thursday? Check out our sister channel SciShow Psych at https://www.youtube.com/scishowpsych!

How would you measure a personality? What, exactly, is the self? Well, as you've come to expect, it's not that easy to nail down an answer for those questions. Whether you're into blood, bile, earth, wind, fire, or those Buzzfeed questionnaires, there are LOTS of ways to get at who we are and why.

--
Table of Contents

Trait & Social-Cognitive Personality 01:35:01
Measuring Personality 02:57:03
Who or What is the Self? 09:16:14
How Self Esteem Works 09:42:04

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So how do we apply the scientific method to psychological research? Lots of ways, but today Hank talks about case studies, naturalistic observation, surveys and interviews, and experimentation. Also he covers different kinds of bias in experimentation and how research practices help us avoid them.
--
Table of Contents

The Scientific Method 2:06
Case Studies 3:05
Naturalistic Observation 3:48
Surveys and Interviews 4:15
Experimentation 6:35
Proper Research Practices 8:40
--
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In which John Green kicks off Crash Course US History! Why, you may ask, are we covering US History, and not more World History, or the history of some other country, or the very specific history of your home region? Well, the reasons are many. But, like it or not, the United States has probably meddled in your country to some degree in the last 236 years or so, and that means US History is relevant all over the world. In episode 1, John talks about the Native Americans who lived in what is now the US prior to European contact. This is a history class, not archaeology, so we're mainly going to cover written history. That means we start with the first sustained European settlement in North America, and that means the Spanish. The Spanish have a long history with the natives of the Americas, and not all of it was positive. The Spanish were definitely not peaceful colonizers, but what colonizers are peaceful? Colonization pretty much always results in an antagonistic relationship with the locals. John teaches you about early Spanish explorers, settlements, and what happened when they didn't get along with the indigenous people. The story of their rocky relations has been called the Black Legend. Which is not a positive legend.

Turn on the captions. You'll like it!

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In which John Green teaches you about the New Deal, which was president Franklin D. Roosevelt's plan to pull the united States out of the Great Depression of the 1930's. Did it work? Maybe. John will teach you about some of the most effective and some of the best known programs of the New Deal. They weren't always the same thing. John will tell you who supported the New Deal, and who opposed it. He'll also get into how the New Deal changed the relationship between the government and citizens, and will even reveal just how the Depression ended. (hint: it was war spending)

Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. President Roosevelt developed his New Deal policies to ease the economic burdens of the Great Depression, a grim reality he began to tackle with his first fireside chat: https://www.commonlit.org/text....s/president-roosevel
In his Economic Bill of Rights, FDR tried to get the country to trust its banks again: https://www.commonlit.org/text....s/the-economic-bill-

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In our final episode of Crash Course Philosophy, we consider what it means to live a good life. We’ll look at the myth of Sisyphus, Robert Nozick’s experience machine, Aristotle’s eudaimonistic picture of a good human life, and the existentialists’ view that we each determine the value of our own lives. And we’ll think about how you, too, can live the life of a philosopher.

Want more Crash Course in person? We'll be at NerdCon: Nerdfighteria in Boston on February 25th and 26th! For more information, go to http://www.nerdconnerdfighteria.com/

Get your own Crash Course Philosophy mug or Chom Chom shirt from DFTBA: https://store.dftba.com/collections/crashcourse

The Latest from PBS Digital Studios: https://www.youtube.com/playli....st?list=PL1mtdjDVOoO

--

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

--

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Venus is a gorgeous naked-eye planet, hanging like a diamond in the twilight -- but it’s beauty is best looked at from afar. Even though Mercury is closer to the sun, Venus is the hottest planet in the solar system, due to a runaway greenhouse effect, and has the most volcanic activity in the solar system. Its north and south poles were flipped, causing it to rotate backwards and making for very strange days on this beautiful but inhospitable world.

This episode is brought to you by Squarespace http://www.squarespace.com/crashcourse

--

Table of Contents
Venus’s Size and Atmosphere 3:09
Hottest Planet in the Solar System 4:04
Slow Clockwise Rotation 6:02
Tremendous Volcanic Activity 8:31

--

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--

PHOTOS/VIDEOS
Naked-eye Venus photo taken by Phil Plait
Phases of Venus http://commons.wikimedia.org/w....iki/File:Phases-of-V [credit: Wikimedia Commons]
2012 Venus Transit https://www.youtube.com/watch?v=34mXua1n_FQ [credit: NASA]
Black drop effect in 2004 http://en.wikipedia.org/wiki/B....lack_drop_effect#med [credit: Vesta]
Venus Transit http://www.nasa.gov/images/con....tent/657111main_1-SO [credit: JAXA/NASA/Lockheed Martin]
Venus in real colors http://en.wikipedia.org/wiki/V....enus#mediaviewer/Fil [credit: NASA]
Earth http://visibleearth.nasa.gov/view.php?id=57723 [credit: NASA Goddard Space Flight Center, Image by Reto Stöckli]
Venus http://www.msss.com/images/sci....ence/venus180hem_mag [credit: NASA/JPL-Caltech/Magellan Project]
Atmospheric Drag on Venus https://www.youtube.com/watch?v=aRAonBSIBck [credit: NASA]
Lakshmi Planum and Maxwell Montes http://en.wikipedia.org/wiki/V....enus_snow#mediaviewe [credit: NASA/JPL]
Artist's impression of the surface of Venus http://sci.esa.int/science-e-m....edia/img/59/VenusSur [credit: ESA]
Venera Images http://planetimages.blogspot.com/ [credit: Ted Stryk]
Venus Globe http://en.wikipedia.org/wiki/V....enus#mediaviewer/Fil [credit: NASA]
Impact craters on the surface of Venus http://en.wikipedia.org/wiki/V....enus#mediaviewer/Fil [credit: Wikimedia Commons]
Idunn Mons http://photojournal.jpl.nasa.g....ov/figures/PIA13001_ [credit: NASA/JPL-Caltech/ESA]
Pancake Volcanoes http://en.wikipedia.org/wiki/P....ancake_dome#mediavie [credit: NASA/Jet Propulsion Laboratory]

In which John Green teaches about filthy, filthy lucre. Money. And Debt. So, what is money? And what is it for? And why do we use money? And why does it all disappear so quickly after payday? John will look into 75% of these questions, and if he doesn't come up with answers, we'll get into some interesting ideas along the way, at least. This week we'll investigate whether money displaces barter, then leads to war, slavery, and what we think of as civilized social orders. We'll also see what old Adam Smith thinks of big money, no whammies, this week on Crash Course.

We'll also talk quite a bit about Debt: The First 5000 Years by David Graeber. You can buy that book here: http://dft.ba/-debt5000

You can directly support Crash Course at https://www.patreon.com/crashcourse Subscribe for as little as $0 to keep up with everything we're doing. Also, if you can afford to pay a little every month, it really helps us to continue producing great content.

In which John Green teaches you about globalization, a subject so epic, so, um, global, it requires two videos. In this video, John follows the surprisingly complex path of t-shirt as it criss-crosses the world before coming to rest on your doorstep, and eventually in your dresser. (Unless you're one of those people who never puts their laundry away and lives out of a laundry basket. If that's the case, shame on you.) Anyway, the story of the t-shirt and its manufacture in far-flung places like China, Guatemala, and India is a microcosm of what's going on in the global economy. Globalization is a bit of a mixed bag, and there have definitely been winners and losers along the way. In this episode John will talk about some of the benefits that have come along with it. Next week, he'll get into some of the less-positive side effects of globalization.

Also, you should turn on the captions.

Thanks to Destin from Smarter Every Day for the cotton footage! http://www.youtube.com/destinws2

Crash Course World History is now available on DVD! http://store.dftba.com/product....s/crashcourse-world-

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Hank tells us about the team of deadly ninja assassins that is tasked with protecting our bodies from all the bad guys that want to kill us - also known as our immune system.

Crash Course Biology is now available on DVD! http://dft.ba/-8bCC

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Table of Contents
1) Innate Immune System 1:45
a) Mucous Membranes 2:54
b) Inflammatory Response 3:44
c) Leukocytes 4:45

2) Open Letter 6:33
a) Natural Killer Cells 6:56
b) Dendritic Cells 7:57

3) Acquired Immune System 8:36
a) Antibodies 9:08
b) Lymphocytes 9:48
c) Cell-Mediated Response 10:17
d) Humoral Response 13:00

References
Campbell Biology, 9th ed.
http://faculty.stcc.edu/AandP/....AP/AP2pages/Units18t
http://highered.mcgraw-hill.co....m/sites/0072495855/s

This video uses the following sounds from Freesound.org:
"Pigs-01.flac" by Erdie
"straw slurp.wav" by dparke4
"Disgusting Slop.wav" by Ighuaran
"Sonar Ping.wav" by digifishmusic
"Swishes.wav" by Pogotron
"swing.mp3" by morgantj

crash course, crashcourse, biology, immune system, anatomy, physiology, human, health, microscopic, pus, pathogen, bacteria, body, organism, virus, immunity, innate, acquired, animal, vertebrate, germ, skin, mucous membrane, digestive tract, mucus, inflammatory response, mast cells, histamine, allergic, allergy, infection, phagocyte, macrophage, natural killer cell, lymphocytes, white blood cells, antigen, t cell, humoral response Support CrashCourse on Subbable: http://subbable.com/crashcourse

Last week we introduced Thomas Aquinas’s four cosmological arguments for the existence of god; today we introduce his fifth argument: the teleological argument, and the ensuing dialogue it initiated.

--

Bokeh Spiral by Eric Wüstenhagen: https://www.flickr.com/photos/eriwst/2987739376
Gusano alambre (wireworms) by jacinta lluch valero: https://www.flickr.com/photos/....70626035@N00/8817671
Experimental by Peter Klashorst: https://commons.wikimedia.org/....wiki/File:Baby_playi
Flightless Cormorant by Mike Weston: https://www.flickr.com/photos/mikeweston/331214460
All other images via Wikimedia Commons, licensed under Creative Commons by 4.0: https://creativecommons.org/licenses/by/4.0/
--

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

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Crash Course Philosophy is sponsored by Squarespace.
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Want more videos about psychology every Monday and Thursday? Check out our sister channel SciShow Psych at https://www.youtube.com/scishowpsych!

***

Not sleeping for days on end. Long periods of euphoria. Racing thoughts. Grandiose ideas. Mania. Depression. All of these are symptoms of Bipolar Disorder. In this episode of Crash Course Psychology, Hank talks about mood disorders and their causes as well as how these disorders can impact people's lives.

--
Table of Contents:

What are Mood Disorders? 1:05
Symptoms of Depressive & Bipolar Disorders 2:00
Biological, Genetic, Environmental, & Social-Cognitive
Causes of Mood Disorders 5:47

--
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Hank takes a break from the desk to bring you to the lab in order to demonstrate some important points about the practical side of chemistry - experimentation in the laboratory. You'll learn what to wear in the lab, how to dispose of chemicals safely, how to avoid the most common accidents, how to pour solutions properly, what the HazMat diamond means, what an MSDS is, and how to use a fume hood. And as a reward for sticking with him through this maybe less-than-thrilling lecture, you'll see Hank subject himself to an exciting piece of safety apparatus.

--
Table of Contents
Proper Lab Attire 0:51
Disposing Chemicals Safely 6:30
Avoiding Common Lab Accidents 5:40
Proper Pouring 5:19
Hazmat Diamond 2:26
MSDS 3:05
How to use Fume Hoods 3:38

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How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early astronomy. Ancient Greeks were able to find the size of the Earth, and from that the distance to and the sizes of the Moon and Sun. Once the Earth/Sun distance was found, parallax was used to find the distance to nearby stars, and that was bootstrapped using brightness to determine the distances to much farther stars.

--

Table of Contents
Ancient Greeks Finding the Size of the Earth 1:07
Earth/Sun Distance Began Our Use of Parallax 5:39
Brightness Relation to Distance 9:07

--

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--

PHOTOS/VIDEOS
Lunar Ecplise http://www.slate.com/content/d....am/slate/blogs/bad_a [credit: Phil Plait]
Venus & Mercury [credit: Phil Plait]
Venus Transit https://www.youtube.com/watch?v=34mXua1n_FQ [credit: NASA]
Black Drop Venus Transit https://en.wikipedia.org/wiki/....Black_drop_effect#me [credit: Wikimedia Commons, H. Raab, Johannes-Kepler-Observatory]
New Horizons Approaching Pluto and Charon https://en.wikipedia.org/wiki/....New_Horizons#/media/ [credit: NASA/JHU APL/SwRI/Steve Gribben]
Radio Telescopes Diagram http://scitechdaily.com/images..../Radio-Telescopes-Se [credit: Alexandra Angelich, NRAO/AUI/NSF]
61 Cygni https://archive.stsci.edu/cgi-bin/dss_search?v=poss1_red&r=21+06+54.60&d=%2B38+44+44.9&e=J2000&h=30&w=30&f=gif&c=none&fov=NONE&v3= [credit: Caltech / National Geographic Society / STScI]
Proxima Centauri https://www.spacetelescope.org/images/potw1343a/ [credit: ESA/Hubble & NASA]
Dying Star http://www.nasa.gov/images/con....tent/64884main_image [credit: NASA, ESA, HEIC, and The Hubble Heritage Team (STScI/AURA)]
Exploding Star http://www.nasa.gov/multimedia..../imagegallery/image_ [credit: NASA, ESA, J. Hester, A. Loll (ASU)]
Animation of a Variable Star http://www.spacetelescope.org/videos/heic1323j/ [credit: NASA, ESA, M. Kornmesser]
Hubble's High-Definition Panoramic View of the Andromeda Galaxy http://hubblesite.org/newscent....er/archive/releases/ [credit: NASA, ESA, J. Dalcanton, B.F. Williams, and L.C. Johnson (University of Washington), the PHAT team, and R. Gendler]