You are right to be confused. And you are in good company. In 1966, Nobel laureate Hermann J. Muller circulated a document containing a number of affirmations about evolution, including the assertion that evolution was a "fact":
An hypothesis is an idea that in science, is subjected to experimental testing. It is the basis of all scientific research. As testing continues and the outcomes of testing are affirmative, an hypothesis evolves into a theory.
A theory is an hypothesis that has survived the rigors of experimental testing over an extended period of time. Facts (lit. things done or seen...observations) are the data that go into the testing of a theory. Although one hopes such data are correct, they are neither necessarily more nor less objective than the theory they are being used to support. And certainly, facts are not as important as the theories they are used to support.
The Harvard astronomer Harlow Shapley illustrates this distinction: "A hypothesis or theory is clear, decisive, and positive but it is believed by none but the man who created it. Experimental findings [facts] , on the other hand are messy, inexact things which are believed by everyone except the man who did the work."
Ann Roe said" I think many scientists are genuinely unaware of the extent, or even the fact of...personal involvement, and themselves accept the myth of impersonal objectivity"
Heisenberg asserted that only observable magnitudes [facts] must go into a theory and chided Einstein that he himself had stressed this in formulating the theory of gravity. Einstein's response was classic: "Possibly I did use this kind of reasoning but it is nonsense all the same. Perhaps I could put it more diplomatically by saying that it may be heuristically useful to keep in mind what one has observed. But on principle it is quite wrong to try founding a theory on observable magnitudes alone. In reality, the very opposite happens. It is the theory which decides what we can observe [the facts]"
Crick has also commented on the role of "facts" in science. From "The Eighth Day of Creation" by H. F. Judson, (Simon and Schuster, NY.1979), Quoting Crick in context:
"They [Bragg, Kendrew, Perutz] missed the alpha helix because of that reflection! You see. And the fact that they didn't put the peptide bond in right. The point is that evidence [facts] can be unreliable, and therefore you should use as little of it as you can. And when we confront problems today, we're in exactly the same situation. We have three or four bits of data, we don't know which one is reliable, so we say, now, if we discard that one and assume it's wrong--even though we have no evidence that it's wrong--then we can look at the rest of the data and see if we can make sense of that. And that's what we do all the time. I mean people don't realize that not only can data be wrong in science, it can be misleading. There isn't such a thing as a hard fact when you are trying to discover something. It's only afterward that the facts become hard."
It is absurd to define evolution as a "fact" without defining what one means by evolution. Evolution can mean anything from a change (no matter how small, or in what direction) in an organism, to molecules-to-man evolution. Few evolutionists bother to draw a distinction between what can be observed (change) and what their theory says could result from that change (molecules-to-man). This is more than an oversight, since it offers a convenient shelter for those who would promote evolution. One can always fall back to the observable (change), when assalted on the theoretical (molecules-to-man).
Some parts of what is encompassed in the term "evolution" are indeed facts. We can observe change in organisms, we can even, by selective breeding, bring about such changes, often much to our benefit.
But molecules-to-man evolution is in another realm altogether. Because it cannot be directly observed, it must be inferred from the most indirect types of evidence. Nonetheless, some evolutionists have difficulty distinguishing fact from fancy as the following quote, from a well-known author, illustrates
There is a critical difference between Copernican theory and evolutionary theory that Gardner appears to have overlooked in his zeal to promote evolution: Copernican theory now has a clear, well understood theoretical basis and mechanism (although properly, it should not be called a "fact"). If one chooses to then suggest that evolution stands on the same footing, it must be shown that evolution also has a clear, well-understood theoretical basis and mechanism, which even Gardner concedes, is not the case. At one time, it was a well established scientific observation [fact] that the sun rotated around the earth. Copernicus challenged this "fact", and suggested the earth rotates around the sun. What would have happened to the advance of science, had Copernicus considered Ptolemaic astronomy to be a "fact"? Gardner falls into the same trap as his evolutionary colleagues who declared evolution to be a "fact".
Compare the attitude of Gardner with this quotation in a lesson on "Science and Pseudoscience" from an interactive educational program by Steven K. Lower:
"Psuedosciences are based largely on dogma and uncritical belief, and hence tend to resist change once they have been developed. Their advocates and practitioners generally regard attempts to alter them as hostile.
"In contrast, skepticism is the very lifeblood of science; it is only by questioning and testing its ideas and theories that new questions are revealed and the science can advance.
"Psuedosciences tend to be fairly static in this regard; the small amount of research and experimentation that is carried out is generally done more to "justify" the belief than to extend it.
"Sciences advance by accomodating themselves to change as new information is obtained.
"In the psuedosciences, a challenge to accepted dogma is often considered a hostile act if not heresy, and leads to bitter disputes or even schisms. In science, the person who shows that a generally accepted belief is wrong or incomplete is more likely to be considered a hero than a heretic."
If evolution were a good theory, its promoters would not want it called a "fact", since therories are far nobler things than "facts". The attempts by Gardner and others to dogmatize evolution as a "fact" are indicators that evolution is closer to a religious belief than many of its promoters would wish to believe.
Richard Feynman in "The Meaning of it All" (p. 28) discusses the importance of understanding the tentative nature if science.
"This freedom to doubt is an important matter in the sciences and, I believe, in other fields. It was born of a struggle. It was a struggle to be permitted to doubt, to be unsure. And I do not want us to forget the importance of the struggle and, by default, to let the thing fall away. I feel a responsibility as a scientist who knows the great value of a satisfactory philosophy of ignorance, and the progress made possible by such a philosophy, progress which is the fruit of freedom of thought. I feel a responsibility to proclaim the value of this freedom and to teach that doubt is not to be feared, but that it is to be welcomed as the possibility of a new potential for human beings. If you know that you are not sure, you have a chance to improve the situation. I want to demand this freedom for future generations.
" Doubt is clearly a value in the sciences. Whether it is in other fields is an open question and an uncertain matter. [...D]oubt is not a fearful thing, but a thing of very great value."
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