Science and Pseudoscience
Critical Thinking
Science
• The scientific method isn’t a complex, or magical process. It’s actually quite mundane!
• It’s how scientists are trained to think that makes science such a powerful tool
Science
• Science relies on:– Skepticism– Critical Thought– The Scientific Method– Imagination!
Science
• Science relies on:– Skepticism– Critical Thought– The Scientific Method– Imagination!
Skepticism
• Which line is longer?
Skepticism
• Which block is darker?
Skepticism
• Skepticism is the practice of not taking the world at face-value but, instead, considering it in close detail before drawing conclusions
Cynicism
• Skepticism is not cynicism• Cynicism:
– Close-minded dismissal of claims that contradict your beliefs
• Skepticism:– Willingness to entertain many possibilities, but
only accepting them after seeing persuasive evidence
Science
• Science relies on:– Skepticism– Critical Thought– The Scientific Method– Imagination!
Critical Thinking
• There is a difference between being critical and criticizing
• Critical thinking is a style of thinking that focuses on careful investigation of phenomena that are not understood, and conservative adoption of new beliefs
• Criticizing (without also providing advice) is just being mean!
Extraordinary Claims
• The more a claim contradicts what we already know, the more persuasive the evidence for the claim must be before we should accept it
Overtoun Bridge
• There is a bridge in Scotland where dogs have been known to commit suicide off of
• Some dogs, which have failed at committing suicide, have even returned for repeat attempts!
Why is this an extraordinary claim?
Falsifiability
• Claims must be capable of being disproved.
Creationism
• Creationism is the belief that the universe is so complex that it could not have been created by mere physical processes, and therefore must have been created by a divine being.
Why can this statement not be falsified? Does this mean it is wrong?
Flying Spaghetti Monsterism
• In 2005, the Kansas City school board attempted to integrate Creationism into science classes
• Critics argued that regardless of whether Creationism is true or false, it has no place in science classes because it cannot be falsified
• One of the more popularized criticisms was the church of the flying spaghetti monster:– http://www.venganza.org/about/open-letter/
Occam’s Razor
• If two hypotheses explain a phenomenon equally well, we should generally select the simpler one.
Occam’s Razor
• Which theory is preferable?
Clocks work through a series of interlocked gears.
Clocks work through a series of interlocked gears
pushed by invisible pink unicornsDoes this mean the Unicorn
theory is necessarily wrong?
Occam’s Razor
• Often what will happen in scientific research is not that we will immediately falsify a theory but, rather, find evidence that supports a more succinct theory
Overtoun Bridge
• The dogs have mostly jumped from one side of the bridge
• Most jumps occurred during clear weather• Most jumpers have been breeds of dogs with
long snouts• A colony of minks were found living in the
foliage under Overtoun Bridge
According to Occam’s Razor, which theory should we prefer? The dog suicide theory, or the mink-hunting theory? Why?
Replicability
• A finding must be capable of being duplicated by independent researchers following the same “recipe”.
Overtoun Bridge
• How could we replicate the mink-hunting theory in a way that would not kill any more dogs?
Ruling out Rival Hypotheses
• Findings consistent with several hypotheses require additional research to eliminate these hypotheses
Overtoun Bridge
• Finally, how could we rule out the dog suicide theory?