Philosophy of Science Notes
Facts and Laws: These are observable events in Nature. Such as:
1. The sun rises in the East and sets in the West.
2. Hold an object in your hand and it will fall to the ground if you let it go.
3. Large fossilized animal bones which are not currently found in any living animal on earth.
4. If you depress the gas pedal of your car, the car will go forward.
Theories: People created explanations of facts and laws. Such as:
1. The sun revolves around the earth (Ptolemy)
The Earth revolves around the sun (Copernicus-Galileo) - This is our current theory
2. All objects fall to their natural resting place. Heavier objects will fall faster than lighter ones (Aristotle)
Large objects attract smaller objects. Objects fall at the same rate no matter size (Galileo-Newton)
Large bodies in space cause a warping of the fabric of space in which objects fall (Einstein) – Current
3. Large lizard-like and cold blooded creatures roamed the earth millions of years ago.
Large lizard-like and warm blooded creatures similar to birds roamed the earth MYA. Current.
4. Pressing on the gas pedal opens a small door and a mouse runs out and runs on a wheel which in turn
makes the car go forward (Mr. Young).
Pressing on the gas pedal forces gasoline into the carburetor…etc.. (the rest of the world). Current.
Falsification: People made theories are always subject to falsification. Falsification occurs when tests on a current theory don’t stand up to more evidence to the contrary. The facts are not subject to change, but the theories are. (Sometimes, however, even facts change – witness a He balloon and gravity)
1. Planets make these strange loops in the sky (called retrograde motion). Also, Galileo noticed that there are moons around Jupiter. If there are moons around Jupiter, then how can we figure that we are the center of the universe? Ptolemy lived around 100 AD. Copernicus around 1540’s. Galileo around 1630’s. In 1992, the Catholic church admits that Galileo was right about a heliocentric solar system.
2. Galileo discovers that large and small objects fall at same rate. Newton (around 1680’s) determines that objects attract each other with a force that varies as inverse to the square of their distance. Einstein theorizes special relativity (around 1920’s). (Here’s a fun one: Not all objects fall – what about a Helium balloon? Helium changes the “facts” associated with gravity.)
3. As we learn more about these fossilized bones, we discover evidence that the bone structure is more similar to birds than to lizards. More evidence needs to be gathered to fill in the picture.
4. We have laws which govern “ideal” gas situations, but we never find that these gases behave in an “ideal” manner. They are often close, but not perfectly in line with our mathematical theories.
5. Upon opening the hood of his car, Mr. Young makes a shocking discovery: There are no mice in there! He now has 2 choices: 1) Claim that “there are mice in there, but you just can’t see them” or 2) change his theory/model of how a car works. (Are dinosaur bones put here to test us? They are not mentioned in the writings of ancient people, so should we choose not to accept their presence in history?)
Bottom line of theories in science:
Science must change its theories in the wake of new evidence, facts or information.
You would be surprised if your science textbook had a copyright date of 300 AD. At that time, we had no idea about the periodic table, about the heliocentric model of the solar system, about the Newtonian laws of gravity or about dinosaurs. A chemistry book with an 1980 copyright date seems “ancient”. (You probably marvel at how anyone survived a hospital in the 1700’s when they didn’t know what a germ was.)
Practical explanations of naturally occurring phenomenon is an on-going and dynamically changing process. It would be unwise to claim that science offers “truth”. It is better to say that science offers a reasonable explanation based on the facts we currently have available to us. No matter our theories, the sun will continue to rise in the East and set in the West. No matter our theories, there are still these large fossilized bones in the ground. No matter our theories, the Earth does not look today at all what it looked like a few hundred years ago (animal species which have died off, geological changes – volcanoes, earthquakes, floods…etc). Change is a natural process both on Earth and in the act of creating scientific theories.
Does Science work as a deductive process or as an inductive process?
Deductive process: A Particular (firm) Conclusion reached from general (not firm) cases
Notice that the facts are stated as “ALL”; no exceptions to the rule.
Fact: All humans are mortal (not firm: because we only know humans to be mortal)
Observation: Socrates is human
Therefore: Socrates is mortal. (firm: because we are predicting that Socrates will ultimately die)
Fact: All dogs bark (not firm: because we only know dogs which bark)
Observation: Snoopy is a dog
Therefore: Snoopy barks. (firm: because we are predicting that Snoopy will bark – but does he?)
Example: (these are firm because we observe them happening. They would be not firm if we said the sun will always rise in the east and set in the west – how could you be absolutely certain that that is true?)
The sun rose in the east and set in the west 10 days ago
The sun rose in the east and set in the west 9 days ago
The sun rose in the east and set in the west 8 days ago
The sun rose in the east and set in the west 7 days ago….etc
Therefore, the sun will always rise in the east and set in the west. (this is not firm because what if tomorrow the sun rises in the west and sets in the east? We will have to change our position).
Example: (these are firm because we observe them happening)
Erica has a TV in her house
Billy has a TV in his house
John has a TV in his house
I have a TV in my house
Susan has a TV in her house…etc.
Therefore, every person has a TV in their house. (this is not firm because what if we go to someone else’s house and discover they don’t have a TV? We will have to change our position)
Science is mostly inductive:
For the most part, science is an inductive process. A scientist gathers firm evidence and then builds a predictive model (theory) around this evidence. It is hard to claim that there are any known “facts” in the world. We are fairly certain that the sun will come up in the East and Set in the West, but really, who knows what tomorrow brings? The results of science are not firm. Science can only predict general (not firm) outcomes based upon particular (firm) facts.
Obviously, it is silly to believe that mice run on a wheel to make my car move. And it is silly to think that everyone has a TV in their house simply because my 10 friends and I have TV’s. But, as scientists we are limited on our ability to make theories based on what we are able to see, feel and hear. If I could not look under the hood of my car, then my theory of mice running on a wheel is perfectly sound. It in no way inhibits my ability to drive. We will never be able to “lift the hood” and see atoms at such a small level that we can understand their entire working process.
If Newtonian mechanics are “incorrect”, well, we were still able to send 12 men to the moon on those 16th century mathematical computations. They were “good enough for government work”.
Bottom Line: Science is people’s creative way of explaining naturally occurring phenomenon. Through the use of these creative explanations (known as theories) we are able to predict other phenomenon and create engineering feats as well (building bridges, going to the moon…etc).
Science will never find the correct explanation for natures’ phenomenon simply because we continue to take in more information every day which helps us modify or completely change our existing theories.