That's not true at all, especially in areas of study where exceptions can be explained within the theory itself. Considering the huge gene pool which exists in the human race, and the mixing of those genes between races, exceptions and such are easy to explain. Also, it's not as if the differences that I'm suggesting for discussion are so far apart.
The truth of the matter is that the mind is such a complex thing, we really don't have the ability to understand or explore the possibilities today.
Scientific inquiry proceeds by formulating a hypothesis in a form that could conceivably be falsified by a test on observable data. A test that could and does run contrary to predictions of the hypothesis is taken as a falsification of the hypothesis
Karl Popper described the characteristics of a scientific theory as follows:
It is easy to obtain confirmations, or verifications, for nearly every theory if we look for confirmations.
Confirmations should count only if they are the result of risky predictions; that is to say, if, unenlightened by the theory in question, we should have expected an event which was incompatible with the theory an event which would have refuted the theory.
Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is.
A theory which is not refutable by any conceivable event is non-scientific. Irrefutability is not a virtue of a theory (as people often think) but a vice.
Every genuine test of a theory is an attempt to falsify it, or to refute it. Testability is falsifiability; but there are degrees of testability: some theories are more testable, more exposed to refutation, than others; they take, as it were, greater risks.
Confirming evidence should not count except when it is the result of a genuine test of the theory; and this means that it can be presented as a serious but unsuccessful attempt to falsify the theory. (I now speak in such cases of "corroborating evidence.")
Some genuinely testable theories, when found to be false, are still upheld by their admirers for example by introducing ad hoc some auxiliary assumption, or by reinterpreting the theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at the price of destroying, or at least lowering, its scientific status. (I later describe such a rescuing operation as a "conventionalist twist" or a "conventionalist stratagem").
One can sum up all this by saying that according to Popper, the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.
Falsifiability (or refutability or testability) is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, it means that it is capable of being disproved under hypothetical circumstances. Falsifiability is an important concept in science and the philosophy of science.
Some philosophers and scientists, most notably Karl Popper, have asserted that a hypothesis, proposition or theory is scientific only if it is falsifiable.
For example, "all men are mortal" is unfalsifiable, since no amount of observation could ever demonstrate its falsehood. "All men are immortal," by contrast, is falsifiable, by the presentation of just one dead man.
Not all statements that are falsifiable in principle are so in practice. For example, "it will be raining here in one million years" is theoretically falsifiable, but not practically.
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http://en.wikipedia.org/wiki/Scientific_method
http://en.wikipedia.org/wiki/Falsifiability
Development of a Simple Theory by the Scientific Method:
Observation: Every swan I've ever seen is white.
Hypothesis: All swans must be white.
Test: A random sampling of swans from each continent where swans are indigenous produces only white swans.
Publication: "My global research has indicated that swans are always white, wherever they are observed."
Verification: Every swan any other scientist has ever observed in any country has always been white.
Theory: All swans are white.
Prediction: The next swan I see will be white.
Note, however, that although the prediction is useful, the theory does not absolutely prove that the next swan I see will be white. Thus it is said to be falsifiable.
If anyone ever saw a black swan, the theory would have to be tweaked or thrown out. Real scientific theories must be falsifiable. So-called "theories" based on religion, such as creationism or intelligent design are, therefore, not scientific theories. They are not falsifiable and they do not follow the scientific method.
http://wilstar.com/theories.htm
According to Stephen Hawking in A Brief History of Time, "a theory is a good theory if it satisfies two requirements: It must accurately describe a large class of observations on the basis of a model which contains only a few arbitrary elements, and it must make definite predictions about the results of future observations". He goes on to state, "any physical theory is always provisional, in the sense that it is only a hypothesis; you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory.
On the other hand, you can disprove a theory by finding even a single observation which disagrees with the predictions of the theory".
http://en.wikipedia.org/wiki/Theory
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