An intro to critical thinking,

skepticism & quirkology

By @RuthEllison

For BarCamp Canberra #3

On 6th February 2010

I’m Ruth

“I help make things easier to

use”

User experience designer

Loves gadgets

Chocolate appreciator

Skeptic-in-training

Work at Stamford Interactive

Loves robots

Live in Canberra

Let me tell you a story about shampoo...

Source: http://www.flickr.com/photos/stirwise/527796228/

A few years back, I received a phone call from The Parents.

There’s this chemical Sodium lauryl

sulfate (SLS)...

This substance is found in most

shampoos...but the fact is that SLS

is used to scrub garage floors, and it

is very strong. It is also proven that it

can cause cancer in the long run.

Source: random emails from around the web

Source: http://www.flickr.com/photos/brainware3000/22205084/

So I did

I replaced it with a special “safe and

effective” product full of “wholesome,

gentle, health-enhancing

ingredients.”*

* Scam alert! Multi-level marketing alert!

A few months later and much

moolah...

I’ve been had!

The Facts

SLS is an irritant

Is not carcinogenic

Sources: http://www.snopes.com/inboxer/household/shampoo.asp; CIR publication. Final Report on the Safety Assessment of Sodium Lauryl Sulfate and Ammonium Lauryl Sulfate. Journal of the American College of Toxicology. 1983 Vol. 2 (No. 7) pages 127-181.

QLD Environmental Health Unit: “SLS

may possibly cause death...if you

ingest approx 5-10kg of

toothpaste”(containing 1% of SLS)

Sources: http://www.health.qld.gov.au/ph/documents/ehu/3368.pdf

Source of image: http://www.colgate.com.au/Colgate/AU/OC/Products/Toothpastes/PDPContent/ColgateAdvancedWhitening/caw_r2_c1.jpg

A skeptic?

Source: http://www.flickr.com/photos/spamily/2181824324/

Skepticism

Isn’t a set of beliefs

It’s a method, not a position1

It’s about critical thinking

Applying methods of science

Respecting good evidence

1 http://www.skeptic.com/about_us/index.html

Some famous skeptics

Penn & Teller (who we got to meet in Vegas)

Richard DawkinsCarl Sagan

Image sources: http://antwrp.gsfc.nasa.gov/apod/image/9612/sagan_uc.gif , http://www.bbc.co.uk/blogs/ni/0701-dawkins-jacket.jpg, http://www.flickr.com/photos/balerini/2532483450/, http://3.bp.blogspot.com/_4ify7vDXrDs/SyrDgTuZbcI/AAAAAAAAE_8/3BLte-9MsGY/s320/James+Randi.jpeg, http://www.skeptic.com/eskeptic/07-09-12images/RWiseman.gif

James Randi Richard Wiseman

What sparked my interest?

Lots of interesting psychological quirks

Watch the video of Richard Wiseman’s

magic card trick (cool quirkology)

http://www.youtube.com/watch?v=voA

ntzB7EwE

Expectations shape our

experience of the world

Mmm, nom nom nom.

What’s happening?

Part of being a

skeptic is

recognising and

compensating

for our biases

Some common cognitive biases

Loss aversion

Imagine that your country is preparing for an outbreak of a disease which is expected to kill 600 people.

Which vaccination schedule will you select?

Program A which will save 200

Program B which will save all 600 with probability 1/3

Source: http://en.wikipedia.org/wiki/Loss_aversion

Imagine that your country is preparing for an outbreak of a disease which is expected to kill 600 people.

Which vaccination schedule will you select?

Program A: which will allow 400 people to die

Program B: no one dies (1/3 probability) or all 600 will die (2/3 probability)

Forer effect: the tendency to give high accuracy ratings to

descriptions of their personality that supposedly are tailored

specifically for them, but are in fact vague and general enough to

apply to a wide range of people source: http://en.wikipedia.org/wiki/List_of_cognitive_biases

Barnum effect: a type of subjective validation in which a

person finds personal meaning in statements that could apply to

many people source: http://skepdic.com/barnum.html

Avoid biases by critically

thinking about the issue

Consider totality of evidence

Ask questions, listen

carefully

Want to learn more?Listen: The Skeptics Guide to the Universe

Skeptoid

Read: Australian Skeptics - www.skeptics.com.auwww.skeptic.comwww.snopes.comWhatstheharm.netModern Skepticism http://www.slideshare.net/reedesau/modern-skepticism-bias-and-the-informed-consensus

www.criticalthinking.orgSkeptic’s Dictionary skepdic.com

Quirkology by Richard Wiseman

Attend: The Amazing Meeting (TAM) in Sydney http://www.skeptics.com.au/latest/announcements/australian-skeptics-announce-tamaustralia2010/

Watch: The People WatchersPenn & Teller’s Bullshit!

Here are additional readings

suggested by attendees of the

session• Richard Dawkins letter to his 10 year old daughter

(how to warn your child about this irrational world) http://www.rationalresponders.com/richard_dawkins_letter_to_his_10_year_old_daughter_how_to_warn_your_child_about_this_irr

ational_world

• Skeptical Sundays to be held shortly in Canberra,

organised by @lozz

• Skeptics in the Pub, held in Sydney on the first

Thursday every month check out www.skeptics.com.au

Ruth Ellison

Email: me@ruthellison.com

Web: www.ruthellison.com

@RuthEllison

Find this presentation at www.slideshare.net/ruthellison

Image sources: http://www.flickr.com/photos/vernhart/1574355646/ , http://randaclay.com/freebies/free-twitter-graphics/