Botkin & Keller Environmental Science 5/e Chapter 2 Science as a Way of Knowing

Botkin & KellerEnvironmental Science 5/e

Chapter 2

Science as a Way of Knowing


Science as Process

• Science is a process of discovery–Scientific ideas change

–Sometimes a science undergoes a fundamental revolution of ideas


Science as Process

• The criterion by which we decide whether a statement is in the realm of science:

Whether it is possible, at least in principle, to disprove the statement.


Disprovability• If you can think of a test that

could disprove a statement, then that statement can be said to be scientific.

• If you can’t think if a test, then the statement is said to be nonscientific.


© 2008 John Wiley and Sons Publishers


Science as Process• Scientific Method:

Actually a set of methods which are the systematic methods by which scientists investigate natural phenomena




Assumptions of Science

• Events in the natural world follow patterns that can be understood through careful observation and scientific analysis.

• These basic patterns and rules that describe them are the same through the universe

• Science is based on a type of reasoning known as induction

• Generalizations can be subjected to tests that may disprove them.

• Although new evidence can disprove existing theories, science can never provide absolute proof of the truth of its theories.


The Nature of Scientific Proof

• Deductive reasoning:– Drawing a conclusion form initial definitions

and assumptions by means of logical reasoning.

• Inductive reasoning:– Drawing a conclusion from a limited set of

specific observations.


Measurements and Uncertainty

• Experimental errors:– Measurement uncertainties and other errors

that occur in experiments.

• Accuracy:– The extent to which a measurement agrees

with the accepted value

• Precision:– The degree of exactness with which a

quantity is measured-how close repeated measurements are to each other


Observations, Facts, Inferences, and Hypotheses

• Observations:– The basis of science, may be made through any of

the five senses or by instruments that measure beyond what we can see.

• Inference:– A generalization that arises from a set of

observations.

• Fact:– When what is observed about a particular thing is

agreed on by all or almost all.



• Hypothesis:– An explanation set forth in a manner that can

be tested and is capable of being disproved.

• Dependent variable:– A variable taken as the outcome of one or

more variables—results from the independent variable

• Independent variable:– The variable that is manipulated by the

investigator; affects the dependent variable.





• Model:– A deliberately simplified explanation of

complex phenomena.– Models are often

• physical• Mathematical• Pictorial or• Computer-simulated





• Theories:– Models that offer broad, fundamental

explanations of many observations




Science, Pseudoscience, and Frontier Science

• Pseudoscience:– Some ideas presented as scientific are in fact

not scientific, because they are • untestable, • lack empirical support, • or are based on faulty reasoning or poor

scientific methodology



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Botkin & Keller Environmental Science 5/e Chapter 2 Science as a Way of Knowing