Natural Philosophy  Socrates, Plato, Aristotle  Were the “authorities” in Western thought from about 500 BCE to 1600 AD  Believed that there was a perfect world, but this world isn’t it

Natural Philosophy  Aristotle’s “perfect world” was accessible only through thought and contemplation.  Observation or experiment on this dirty, nasty imperfect world was useless in understanding “timeless truth.”

Beginnings of Science  Science, as we know it, evolved from “natural philosophy” (literally “thinking about nature”) starting about the year 1600 due to the work of Galileo, Bacon, and many others.

Scientific Progress  In the last 400 years, scientists have made incredible strides in their efforts to understand our universe (although there is still much to know).  Scientific progress has brought about technological progress that Galileo could not have imagined.

Scientific Methods  “The success of science has more to do with an attitude common to scientists than with a particular method. This attitude is one of inquiry, experimentation, and humility before the facts.”  Ideas Worth Sharing Ideas Worth Sharing

Science Terminology  We need a common science vocabulary in order to communicate effectively with one another.  Keep in mind that the scientific meaning of a word is often different than its everyday meaning.

Steps in the Scientific Method  Question/Problem  Observation/Inference  Hypothesis  Experimental Design  Methods  Procedure  Results  Data Collection  Data Analysis  Conclusion  Further Research  Retest etc.

Observation  An observation is something you notice.  May be casual or even accidental  May be formal - experimental data are observations.  You make an observation based on your senses- sight, sound, hearing, taste etc.  Not all observations are correct - people make mistakes.

You Try Observing…

1. Where there any cars on the side of the street? 2. What color is the pick up truck driving in the road? 3. Were there any mini vans around? 4. What does the blue sign say? 5. What is the speed limit? 6. Are there any pedestrians on the road?

You Try Observing…  Answers: 1. Yes 2. Blue 3. Yes 4. Yard Sale mph 6. No

Scientific Inference  Logical interpretation based upon prior knowledge and experiences  Based upon observations  Example: On the first day of school when you entered the room, you most likely inferred that the individual in the front of the room was the teacher.

Problem/Question  A problem/question is formed based on observations and inferences  Must be testable  Can ask what, why, how  Example: Why is the sky blue?  How do trees grow so big?  What happens when…..

Hypotheses  A hypothesis is a possible explanation as to why something happens.  Most likely written in the If….then.. Because… form  A scientific hypothesis must be testable by observation - there must be observations that we can make to tell whether the hypothesis is correct or not.  If (we perform this experiment), then (this is what is going to happen), because (we found this out based on our research.)

Experimental Design  A set of materials needed to conduct the experiment  A detailed list of steps used to test the hypothesis.

Scientific Experiments Follow Rules: Variables  An experimenter changes one factor (independent variable) and observes or measures what happens (dependent variable).

The Control Variable/Group The experimenter makes a special effort to keep other factors constant so that they will not effect the outcome. The experimenter makes a special effort to keep other factors constant so that they will not effect the outcome. Those factors are called control variables. Those factors are called control variables.  Controls are NOT being tested  Controls are used for COMPARISON

Other Variables  The factor that is changed is known as the independent variable.  The factor that is measured or observed is called the dependent variable.

One more thing… it is best to make several trials with each independent variable.

Data  Results of the experiment  May be quantitative (numbers) or qualitative (based on descriptions)  If numbers are used, they must be measured using the metric system!

Conclusions  A conclusion is a decision based on observations, facts, and experimental data.  It explains what happened and provides an explanation as to why it may have happened.

Further Research  Future Research must be addressed.  Describes possible experiments that could be completed in the future based on your conclusions.

Scientific Laws  A scientific law is a powerful summary of many facts.  Laws describe what happens, they don’t generally explain why they happen.  Laws can often be expressed very conveniently and concisely in mathematical form.

Scientific Theories  As experimental evidence (observations) accumulates, we can become more confident that a hypothesis is true.  A theory is a synthesis (powerful combination) of well-tested hypotheses.  Scientific theories tend to explain why scientific laws operate the way they do - theories are often called “models”.  Fun Fact: The word “theory” is probably the most misused science term - certainly by laymen, but even by scientists!

The Process of Science  In science NOTHING (well, hardly anything) is ever “proven once and for all”.  This process of testing facts, conclusions, laws, and theories with experimental observations NEVER ENDS.

Steps in the Lab Report  Abstract  Summary of the experiment  Background Information  Mention previous studies  Major findings of research  Question/Problem  Based on observation  Experimental Design  Materials/procedures  Data  Data Analysis  Discussion  Further Research  Works Cited

The End