- Empirical facts: supported by direct, straightforward, observational evidence. For example, a
pencil on a desk. You can see, feel, hear, taste and smell it (if you wanted).
- Now you have another pencil, same situation. But you put it in a drawer. You cannot see it
there, but you believe it is there. This belief cannot be the same as believing the pencil on the
desk. After all, you cannot see, touch, or observe it in the drawer.
- This is because most of us cannot imagine that objects go out of existence when they are no
longer observed. Stable objects remain in existence without being observed.
- The pencil on the dust is direct observational evidence while the other stems from our views on
the world we live in.
- A scientific theory has relevant facts but theories from the history of science are based on
philosophical/conceptual convictions about the sort of world people involved inhabited.
- Example: from ancient Greece to the early 1600s, people believed plants moved w perfectly
circular and uniform motion at the same speed. Our current theories, for ex. Mars, shows that it
moves in an elliptical orbit and at varying speeds.
- At first, the initial beliefs were “obvious” because “ether” moved perfectly circular; this
everything within ether would do the same. These facts are heavily philosophical.
- Empirical/philosophical and conceptual facts are not absolute. Most beliefs are a mixture. Ex.
People observed stars moved perfectly circular, this empirical as well.
- It is better to think in terms of a continuum. At one end, straightforward, and at the other,
A note on Terminology
- We do not have the right word to properly characterize deeply held and justified beliefs, such as
“perfectly uniform” and “circular motion” (because they are not factual anymore)
- They are not assumption either because they are based on the overall view of the universe we
- Strongly held beliefs appear to be facts. Best terms: empirical/philosophical facts
- Approx. 100 years ago Einstein proposed the general theory of relativity. It predicted that the
gravitational effect of a large body (the sun) would bend starlight. This was found true during
the solar eclipse of 1919.
- This reasoning is not unique to science. When we base predictions and they turn out to be
correct, this is evidence that the theory is correct. - If we use T o rep a theory and O to rep observations predicted by T, then we can rep this as
follows: if T, then O so O/T.
- Late 1980s, cold fusion theory. If cold fusion was correct, one would expect a very high number
of neutrons to be emitted during the process. Yet, expected # was not detected and this was
evidence against this theory.
- When we make predictions about a particular theory and those are not correct, we take it as
- Again, using T and O: if T, then O. so NOT O/NOT T
Inductive and Deductive Reasoning
- Confirmation reasoning = inductive. Disconfirmation = deductive.
- Some say inductive moves from specific to general and deductive, vice versa. Not accurate!
- Example of inductive: College men’s ball team never won NCAA. When they do make it to the
tournament, they do not make it past the 1 round. This year, nothing has changed about the
program. These factors make it unlikely that they will win the NCAA this year.
- Given the premises of the argument, the conclusion is likely. BUT even if all premises and
evidence are correct, it is still possible that the conclusion may be wrong. It is still possible that
the men can win this year!
- Inductive reasoning: in a good inductive argument, even if all premises are true, it is possible for
the conclusion to be wrong.
- Deductive argument: true premises guarantee a true conclusion.
- Ex. whoever was in Linda’s house killed Linda. Whoever killed Linda is Uri. Commander Farrell
was in her house. Therefore Commander Farrell is Uri.
- Confirmation reasoning can best provide support for a theory but it will always remain possible
that the theory is mistaken due to its inductive nature.
- Consider the bending starlight theory. In order to do necessary calculations to predict the
position of bent vs. unbent starli