Science and the Scientific Method

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Science and the Scientific Method

• An Introduction for Paramedic Students

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What is Science?

• A set of facts and the theories that explain the
  facts.

Science

• Whatevers being done by institutions carrying on
  scientific activity.

• A particular approach, the scientific method.

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Popular Fictions

• The goal of science is to accumulate facts
• Science distorts reality and cant do justice to
  the fullness of human experience.
• Scientific knowledge is truth.
• Science is concerned primarily with solving
  practical and social problems.

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So then, what is Science?
Science is neither a philosophy nor a belief
system. It is a combination of mental operations
that has become increasingly the habit of
educated peoples, a culture of illuminations hit
upon by a fortunate turn of history that yielded
the most effective way of learning about the real
world ever conceived.
Edward O. Wilson Consilience The Unity of
Knowledge
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The Heart of the Matter
Why do we see what we do and not something else?
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Explanation
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Mythos
The Word
An authoritative account of the facts that is not
to be questioned.
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Thales of Miletus

• The Father of Greek Science, Philosophy, and
  Mathematics
• Man is capable of understanding nature.
• Natural phenomena have natural explanations.

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Logos

• The Word
• An account of the facts whose truth can be
  demonstrated and debated

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Aristotle

• Developed logos into logic
• Advocated deductive reasoning as a tool for
  understanding nature
• Dominated scientific thinking for the next 2000
  years

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Deduction

• Reasoning from the general to the specific
• All men are mortal. (major premise)
• Socrates is a man. (minor premise)
• Therefore, Socrates is mortal. (conclusion)
• Always produces correct answers if the premises
  are correct.

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The Problems of Deduction

• The conclusions are only as good as the premises.
• Because it moves from general to specific cases,
  deduction does not generate new knowledge.

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The Problem with Aristotle

• He didnt advocate the use of experiments or
  observations to check the validity of premises.
• He was a pure rationalist.
• Thinking about it is good enough.

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Francis Bacon

• If you want to know how the world works, begin
  with the facts. Not prejudices about what the
  facts are.
• Infer general instances from specific
  observations.
• Draw conclusions about future events from past
  observations.

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Induction

• Reasons from the specific to the general
• Can generate new knowledge
• However, the accuracy of that new knowledge can
  NEVER be proven with 100 certainty

WHY?
Because we can never be 100 certain about what
our next observation will show
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Galileo

• If you have a theory about how a phenomenon
  works, test it with an experiment.
• During an experiment, try to control all of the
  variables except the one you are interested in.

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Isaac Newton

• Mathematics is the language of nature.
• The world of observation can be encoded into
  mathematical form.
• Mathematical forms can be decoded into new
  statements about reality.

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The Scientific Method
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Hypothesis
Empirical Law
Observation
Experiment
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Empirical Laws

• Are about kinds of events, not any single event
• Show relationships between two or more kinds of
  events
• Are supported by a large amount of experimental
  data
• Are applicable to a variety of different events

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An Example Boyles Law

• In 1662, Irish chemist Robert Boyle studied the
  effects of pressure changes on the volume of
  gases.

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An Example Boyles Law

• His experimental results showed that as pressure
  increases, the volume of a gas decreases
  proportionately.
• PV constant
• So, if we decrease the volume of a container, we
  can predict how much the pressure of the gas
  inside will increase.

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An Example Boyles Law

• Boyles work was later combined with that of
  Jacques Charles and Joseph Gay-Lussac to produce
  the Ideal Gas Law.
• PV nRT
• The Ideal Gas Law predicts the behavior of gases
  over a wide range of temperatures, pressures, and
  volumes.
• Theres just one problem

It doesnt explain how this stuff works!
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We need a theory!!!

• A means of relating the laws describing a class
  of events to a framework and a set of principles
  described in terms differing from those used for
  the laws.
• The observations predicted by the Ideal Gas Law
  are explained by the Kinetic Theory of Gases.

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The Kinetic Theory of Gases
Lets assume that the molecules making up a gas
are like little billiard balls...
Wouldnt that make the gas pressure equivalent to
the number of impacts by the billiard balls with
the sides of the container?
So, if we decrease the size of the container,
what happens to the number of impacts?
What would happen to the number of collisions if
we increased the velocity of the billiard balls?
Isnt increasing the velocity of the billiard
balls equivalent to increasing the temperature of
the gas?
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The Kinetic Theory of Gases
Theory of Billiard Balls
Kinetic Theory
MODEL (Tiny elastic spheres)
Observations on Gases
Observations on Billiard Balls
Analogy?
Analogy?
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A Good Theory Is...
Accurate
Fruitful
Consistent
Simple
Broad
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Why there are no scientific truths
The Problem of Induction
Hypotheses, laws, and theories are products of
inductive reasoning
Products of inductive reasoning are only as good
as the next observation
But it only takes one negative piece of data to
refute it
So, no amount of data will ever confirm a
hypothesis, law, or theory
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Falsifiability
The scientific mentality may be roughly
characterized as the tendency to suspend belief
until evidence of the appropriate kind is
produced. And then to believe the proposition in
question to the degree that the available
evidence warrants it, without excluding the
possibility of a further disconfirmation.
Sir Karl Popper
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Norms of Science
Originality
Accessibility
Detachment
Skepticism
Universality
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The Hallmarks of Pseudoscience
Seeking Mysteries
Anachronistic Thinking
Appeals to Myths
Irrefutable Hypotheses
Casual Approach to Evidence
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The Hallmarks of Pseudoscience
Spurious Similarities
Refusal to Revise
Explanation by Scenario
Research by Literary Interpretation
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Eight Important Points

• Anecdotes do NOT make science
• Scientific language does NOT make science
• Bold statements do NOT make claims true
• Heresy does NOT equal correctness

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Eight Important Points

• Rumors do NOT equal reality
• Unexplained is NOT inexplicable
• Correlation does NOT mean causation
• Coincidence does NOT mean connection

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Always remember...

• A wise man proportions his belief to the
  evidence.

David Hume