Nature of Science
Science
the systematic approach for acquiring knowledge about the world around us
The process for learning about the world relies on objective observation and experimentation,
comparison with related knowledge and expectations, and logical deductions.
Pure Sciences
Technology
the goal is the understanding the world
Experimental Sciences: Astronomy, Biology, Chemistry, Geology, Physics
the application of science knowledge for a specific purpose
The process of design and use of devices, processes, and materials to solve practical problems.
Tools, fire, machines, generators, microscopes, apps, computer programs, plastics, Kevlar, sneakers
Applied Sciences
the goal is the development of better processes and products to solve problems
Engineering, medicine and computer science are applied sciences
Social Sciences
the scientific approach to understand the relationships and behaviours of
individuals and groups
anthropology, archaeology, criminology, economics, education, political science,
geography, law, psychology.
In modern times, an understanding of the underlying science is the basis for technological developments.
These new technologies in their turn drive developments in science.
Scientific Method and the Development of Scientific Knowledge
The Scientific Method
the controlled, systematic approach to learning about natural phenomena.
This method consists of several distinct steps that can be adjusted and repeated in an effort to
understand better and get closer to the “truth”.
The steps include observation, prediction, experimentation, and conclusion.
The first step is often observation and recognition of a pattern or an anomaly.
Observation
can be quantitative (measured) or qualitative (described using words).
Prediction
expected result based on accepted scientific knowledge and personal experiences
 not a “wild guess” that lacks logical reasoning
Experimentation a well-designed test in which all significant variables that could affect the result are kept
constant except for the one independent variable whose effect is being tested.
Dependent Variable (y) is the characteristic that is being observed or measured; responding variable
 changes in the dependent variable depend on changes in the independent variable
Independent Variable (x) is the property that is being changed during the experiment; manipulated variable
Control Variables are all of the variables that could affect the dependent variable that are kept constant or
within a small range
Conclusion
the interpretation and evaluation of the results and comparison with the prediction
General trends and anomalies should be noted and explained.
Further predictions can be made based on these trends and exceptions.
While a systematic approach using a logical series of steps is effective more consistently, many significant
scientific discoveries and ideas have resulted from serendipity and intuition.
Serendipity
the discovery of something more important while searching for something else.
 nuclear radiation, penicillin, photoelectric effect
Intuition
the natural ability to know something without any proof, evidence, or logic
Newton (apple), Kekule (benzene), Archimedes (gold)
According to Einstein:
"The intellect has little to do on the road to discovery. There comes
a leap in consciousness, call it Intuition or what you will, the
solution comes to you and you don't know how or why".
Scientific Knowledge
Scientific knowledge requires evidence that can be tested.
Scientists must adopt a skeptical attitude to claims rather than having blind faith
 suspend judgment until they have a good reason to believe a claim to be true or false.
Such reasons are based on reliable evidence and argument.
Experimental Evidence
observation of the results from a controlled experiment, usually in a lab
 mostly physics and chemistry
Observational Evidence
direct observations using the senses or using instrumentation and sensors
 Darwin’s observations, most astronomy and large-scale geology
This evidence is used to develop theories, generalize from data to form laws and propose hypotheses.
These theories and hypotheses are used to make predictions that can be tested.
In this way theories can be supported or opposed and can be modified or replaced by new theories.
Hypothesis
a prediction and explanation that is based on observation, scientific principles, and logic.
An hypothesis usually applies to a specific situation and has yet to be widely tested or widely accepted
Theory
a set of scientific hypotheses and principles that explain and predict phenomena.
A theory must:
• be widely accepted in the scientific community
• have been supported with repeated testing
• be applicable to a wide variety of related phenomena
Basically, if evidence accumulates to support a hypothesis, then the hypothesis can become accepted as a
good explanation of a phenomenon. One definition of a theory is to say it's an accepted hypothesis
A theory is valid as long as there is no evidence to dispute it.
A theory cannot be proven; it can be supported or it can be disproven.
ex.
Law
Big Bang theory, atomic theory, continental drift theory
theory of evolution, quantum theory, theory of relativity
generalizes a body of observations.
At the time it is made, no exceptions have been found to a law.
Scientific laws explain things, but they do not describe ‘why’ they happen.
http://chemistry.about.com/od/chemistry101/a/lawtheory.htm
ex.
Model
Law of Universal Gravitation
Ideal Gas Laws
Law of Superposition
Law of Segregation
Law of Conservation of Mass-Energy
Newton’s Laws of Motion
a simplified representations of one or more aspects of a physical phenomenon
used to communicate ideas and to test an hypothesis
limited by their simplifications and exclusion of important variables
ex.
Rutherford’s atomic model
Cell model
Solar system
Plate boundary interactions  earthquakes, volcanoes, mountains, ocean basin lifecycle
Science Disciplines
Disciplines
 large, well-defined areas of knowledge
 have a unique subject area and approach to their subject
 are subdivided into large unique subject areas
 have laws, theories, models, and terminology that distinguish each discipline from others
Astronomy
the study of the world beyond the Earth’s atmosphere
Biology
the study of living things and their interactions
Chemistry
the study of the composition and properties of matter and its changes.
Geology
the study of the origins, structures, processes, and composition of the Earth.
Physics
the study of the physical world.
“All science is either physics or stamp collecting.” – Rutherford, 1962