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Area of Knowledge Natural Science

…it goes way beyond defying the “I before E except after C rule.”

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Area of KnowledgeNatural Science

…it goes way beyond defying the “I before E except after C rule.”

Science The body of knowledge about

nature that represents the collective efforts, findings, insights, and wisdom of the human race.

A human activity, with the functions of discovering the orderliness of nature and finding the causes that govern this order.

Henri Poincaré (1854-1912)

Science is built of facts, as a house is built of stones: but an accumulation of facts is no more a science than a heap of stones is a house.

Science

Process: The Scientific Method

Known Information about Nature: Scientific Laws and Theories

Scientific Method

Recognize a problem Make observations - Collect data Form a hypothesis (must have a

test for falseness) Perform experiments Form conclusions - Theory

Making observations (My car will not start.)

Suggesting a possible explanation, called a hypothesis, that is consistent with what has been observed ("My car will not start because it is out of fuel" - Hypothesis 1.)

Using the hypothesis to make predictions (If I add fuel to my car it will start.)

For Example:

Testing those predictions by experiments or further observations (Add fuel to the car and try to start it). ( Car still will not start).

"My car will not start because there is a fuel blockage" - Hypothesis 2

Modify the hypothesis in the light of new observations and results.

Use the hypothesis to make predictions (If I clean out the fuel line my car it will start.) Test those predictions by experiments or further observations. Experiment: I clean out the fuel line and the car starts.

I conclude that my car wouldn’t start because its fuel line was clogged.

The Scientific Method (In the real world)

Research - Experiments, Data, Conclusions, Supporting Evidence

Submit to Scientific Journal Journal submits paper to

anonymous referees – peer review Referees study paper, make

suggestions & judgements Rework paper as needed.

Resubmit to Journal Journal Publishes Paper: Paper now

“fair game”

The test of all scientific knowledge and truth is experiment.Richard Feynman

Scientific inquiry differs from other human inquiry in the kind of evidence scientists pay attention to.

Scientific evidence must be replicable and falsifiable. It must be shared evidence and thus, independent of the inquirer’s personal and cultural perspectives.

It’s all about evidence!

We used to teach that scientific evidence must be verifiable. 1902-

1994

Falsifiability

The philosopher Karl Popper turned around this thinking arguing that the criterion is falsifiability.

Scientific evidence must be replicable and falsifiable.

Falsifiable: Capable of being shown to be not true. Refutable, Testable.

Replicable: Capable of being done by others, giving the same results.

In a landmark 1993 decision, the U.S. Supreme court put it this way:

… the criterion of the scientific status of a theory is its falsifiability, or refutability or testability”

“Scientific methodology today is based on generating hypotheses and testing them to see if they can be falsified; indeed this methodology is what distinguishes science from other fields of human inquiry…

Which of the following is a scientific statement?

1. There are forces in the universe that are undetectable and so we will never know about them.

2. The Universe is only 3 hours old, but was created to appear much much older. We were created with our memories intact. 3. The Earth is not exactly spherical, as it is actually a bit wider at the equator.

Hypotheses are educated guesses about what the answer might be, and can be useful throughout the inquiry. Like evidence, they must be testable and relevant to the question being asked. If the test validates the guess, great… if not, the scientist faces a critical decision: give up on a favorite conviction or keep going.

Hypothesis Testing

Hypotheses are falsified when the evidence supporting them cannot be replicated.

Watson and Crick’s double helix is an example of a hypothesis. It was tested, and not falsified, by Rosalind Franklin’s x-ray diffraction observations.

      “It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong” W. French Anderson -- the first scientist to cure a

disorder through gene therapy

"The great tragedy of Science: the slaying of a beautiful hypothesis

by an ugly fact" Thomas Henry Huxley

Science

“Look at the ideas themselves and judge them directly. Do not accept them on the basis of authority. Question, Question, Question, especially your own ideas. Look at problems from all angles. Try to determine what is wrong with your solution before someone else does.”

Richard Feynman

A “Theory” is used in everyday English to mean hypothesis whereas in science it means something much stronger.

Theories, Facts, and Laws

In scientific terms, “theory” does not mean “guess” or “hunch.” Scientific theories are explanations of natural phenomena built up logically from testable observations and hypotheses.

Theories are backed with solid data from many published scientific experiments, over time, that continue to support it as the best explanation thus far.

A theory can never be proven to be correct.

Theories, Facts, and Laws

Scientists most often use the word “fact” to describe an observation. But scientists can also use fact to mean something that has been tested or observed so many times that there is no longer a compelling reason to keep testing or looking for examples.

Theories, Facts, and Laws

Laws are generalizations that describe phenomena. Whereas, theories explain phenomena.

For example: Newton’s Law of Gravity – describes how gravity

behaves

Einstein’s Theory of Relativity – explains how gravity works Theories never become a laws.

In our present world, research scientists are fighting to reinforce to the non-scientific world that the “theory of global climate change” and the “theory of evolution” (to name two hot-topic theories) are not mere guesses or hunches, but explanations based on reliable data that should be taken seriously.

Global Climate Change

“It’s only a theory”

Everyone’s talking about global climage change… Should YOU be concerned?

Climate change is one of the most critical global challenges of our time. Recent events have emphatically demonstrated our growing vulnerability to climate change.

Climate naturally changes across geologic time, but the current RATE of change is unprecedented. The only thing in our computer models that can accurately explain this is the anthropogenic component (man-made emissions).

Climate change impacts will range from affecting agriculture further endangering food security, sea level rise and accelerated erosion of coastal zones, increasing intensity of natural disasters, species extinction and the spread of tropical diseases (e.g. malaria).

…But if you don’t want to accept this “knowledge by authority,” then check out the empirical evidence on your own.

…Sea Level Rise

Why can’t climate scientists predict the future with greater certainty?

Just consider “simple” weather prediction…

“Imagine a system on a rotating sphere that is 8000 miles wide, consists of different materials, different gases that have different properties (one of the most important of which, water, exists in different concentrations), heated by a nuclear reactor 93 million miles away. Then, just to make life interesting, this sphere is oriented such that as it revolves around the nuclear reactor, it is heated differently at different locations at different times of the year. Then, someone is asked to watch the mixture of gases, a fluid only 20 miles deep, that covers an area of 250 million square miles, and to predict the state of that fluid at one point on the sphere 2 days from now. This is the problem weather forecasters face.”

Robert T. Ryan. “The Weather is Changing… or Meteorologists and Broadcasters, the Twain Meet,” Bulletin of the American Meteorological Society, 63, no. 3 (March 1982), 308.

“Science does not deal in certainty, so ‘fact’ can only mean a proposition affirmed to such a high degree that it would be perverse to withhold one’s provisional assent”

Stephen Jay Gould

Further complications… "A good model should be simple and it should exhibit the behaviors

of the real system that interests us...it should suggest experimental tests of itself that are so revealing that we must eventually discard the model in favor of a better one. We therefore measure scientific progress by the production of better and better models, not by whether we find some absolute truth...

“Truth is elusive, but we can gradually approximate it by creating better and better representations. There are at least two reasons why the truth is elusive in real systems...

“The universe is extremely complicated...second, we tend to change reality when we examine any system too closely. The disturbances that inevitably accompany all observations will change the thing being observed. Thus "truth" will be changed by the very act of looking for it...what is really important is the progress of the search, rather than some ultimate explanation that is probably unattainable anyway.“

Excerpts from Mathematical Biology by Shonkwiler, Ronald W.; Herod, James, published by Springer. pp. 1-8

Science in the Movies

Extraordinary claims require extraordinary evidence.

“For all I know we may be visited by aliens every other Tuesday. Yet, the fact is, there is not a shred of hard physical evidence to support even a single visit. There’s often the reports of evidence, but never the evidence itself.”

Carl Sagan

Pseudoscience

Astrology

Faith Healing

Intelligent Design

Dousing

Creation Science

Channeling

Pyramid Power

Crop Circles

Etc.

Science

Physics

Chemistry

Biology

Geology

Astronomy

Etc.

We offer a one-million-dollar prize to anyone who can show, under controlled conditions, evidence of any paranormal, supernatural, or occult power or event.

We do not involve ourselves in the testing procedure, other than to design the protocol and approving the conditions under which a test will take place. All tests are designed with the participation and approval of the applicant. In most cases, the applicant will be asked to perform a relatively simple preliminary test of the claim, which if successful, will be followed by the formal test.

Million Dollar Prize

Million Dollar Prize

The only thing the JREF asks of you in defending your claim, is to demonstrate it. No theories, no stories, no anecdotal evidence, no photographs, no tape recordings; just a simple demonstration. Nothing more is required

Preliminary tests are usually conducted by associates of the JREF at the site where the applicant lives. Upon success in the preliminary testing process, the "applicant" becomes a "claimant."

To date, (Prize Started in 1964) no one has ever passed the preliminary tests.

Million Dollar Prize

Elementary Logic Errors:An important part of scientific thinking is being able to recognize non-scientific thinking. Examples include…

Circular Reasoning:

Ralph Nader was the best candidate for president, because he was totally better than any of the others.

If the mill were polluting the river we would see an increase in fish deaths.

Fish deaths have increased.

Thus, the mill must be polluting the river.

Non-sequitor

(it does not follow):

Elementary Logic Errors:An important part of scientific thinking is being able to recognize non-scientific thinking. Examples include…

Non-sequitor

(it does not follow):

Abraham Lincoln is dead.

All Incas are dead.

Therefore, Abraham Lincoln is an Inca.

Elementary Logic Errors:An important part of scientific thinking is being able to recognize non-scientific thinking. Examples include…

Ad hominem arguments:

(Against the Man)

Stem cell research is morally wrong, and the only reason you defend it is that you’re a godless atheist.

Elementary Logic Errors:An important part of scientific thinking is being able to recognize non-scientific thinking. Examples include…

Do we get anything useful from

science?

Should our research have an application, or do we do science for

the sake of the knowledge alone???

The really cool thing about science is how well it works! (Science & technology)

Human Longevity

0

20

40

60

80

100

-200 300 800 1300 1800

Date (Year)

Av

era

ge

Lif

es

pa

n

PresentBut perhaps this is skewed…

Queen Anne1665-1714

In the last 17 years of the 17th century (1683-1700) she was pregnant 18 timesOnly 5 of these resulted in live births.Only 1 of these 5 survived infancy…but he died before reaching adulthood

“I am no witch. I am innocent. I know nothing of it.”

Bridget Bishop

Non-scientific thinking ending in tragedy:Bridget Bishop Was the First to Go

…Salem 1692

Last State Executions for Witchcraft…Holland 1610

England 1684

United States 1692

France 1745

Germany 1775

Poland 1793

Italy (Inquisition) 1816

“The only thing that stands between us and burning witches is science”

Carl Sagan

Today, in the city of Kinshasa, the capital of the Congo, there are an estimated 25,000 homeless children. Sixty percent of them are homeless because they have been thrown out of their homes and branded as witches by their relatives. L.A. Times 9/29/06

Science & Religion

The methods of science and religion are profoundly different. Religion frequently asks us to believe without question, even (or especially) in the absence of hard evidence. Indeed, this is the central meaning of faith.

Science asks us to take nothing on faith, to be wary of self-deception, to reject anecdotal evidence.

Science considers deep skepticism a prime virtue. Religion often sees it as a barrier to enlightenment.

“I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forego their use.”

Galileo

All our science, measured against reality, is primitive and childlike --- and yet, it is the most precious thing we have.

Albert Einstein

(1879-1955)

But can we ever know it all???

Heisenberg Uncertainty Principle

Heisenberg Uncertainty Principle explained…

But can science even attempt to explain everything that is important?