1. Testimonials Plausibility

2. Research is probabilistic

3. Research reveals tendencies

4. Single cases can be found in support of any belief

5. Single cases can be found to refute any claim

6. How much data before the tendency is revealed?

8. Testimonials – even large numbers of people can be wrong

9. Homeopathy History – from humours to dynamic system Today – 100K physicians, 500M patients Drugs – 3K drugs, including Rabies! Machines: James Randi video - http://www.youtube.com/watch?v=BWE1tH93G9U http://www.youtube.com/watch?v=BWE1tH93G9U

10. Self-Deception How can an honest person mistake worthless treatment for one that works? We are going to talk about 10 Competing Explanations

11. 10 Competing Explanations The Placebo Effect The simple expectation of recovery sometimes has a positive effect

12. 10 Competing Explanations Spontaneous Remission Sometimes diseases disappear without any treatment

13. 10 Competing Explanations The Disease Ran its Natural Course If a disease is not chronic or fatal, it may be self- limiting

14. 10 Competing Explanations The Cyclical Nature of Many Diseases Even chronic conditions go through phases

15. 10 Competing Explanations Misdiagnosis There may be no disease in first place

16. 10 Competing Explanations The Worried Well Some people with no disease nonetheless seek health care

17. 10 Competing Explanations Symptomatic Relief Alleviation of symptoms does not necessarily mean the disease has been cured

18. 10 Competing Explanations Hedged Bets People sometimes simultaneously receive evidenced-based health care

19. 10 Competing Explanations Derivative Benefits Purely psychological benefits can lead to people taking better care of themselves

20. 10 Competing Explanations Psychological Distortions of Reality Cognitive dissonance can distort perceptions of the effectiveness of treatment

21. Cognitive Dissonance Cognitive dissonance is a psychological term which describes the uncomfortable tension that comes from holding two conflicting thoughts at the same time. To reduce the dissonance, people modify one of the two thoughts, or invent new thoughts

23. UFOs Some respectable people believe in UFOs http://www.youtube.com/watch?v=bQgfaLFTl4U Its world-wide http://www.youtube.com/watch?v=DbSSTqlanS8 Some sightings defy explanation http://www.crowdedskies.com/ufo_videos.htm Some sightings appear like hoaxes http://www.youtube.com/watch?v=T67TkiyEOXg Some sightings are pretty cool! http://video.google.com/videoplay?docid=7027173637881161714

24. Alien Abductions Alternative explanations Contamination Effect Sleep paralysis NOVA Kidnapped by UFOs? http://www.pbs.org/wgbh/nova/aliens/