Wednesday, December 12, 2007

Evolution as fact...

Okay. I had a disagreement with J the other day about whether or not evolution is a fact. He supports evolution, but claimed that the fact that something is happening doesn't make it a fact. His example was, "if you call someone and tell them I'm at the pizza place, then it's not necessarily a fact to them." (But that doesn't matter because regardless of whether or not that person believed he was at the pizza place, he'd still be at the pizza place)

Another person I talked to agreed with him, stating that the definition of fact mentioned the word truth and she argued that evolution cannot be proven to be an ultimate truth. (But what can? Can't we even argue our own non-existence under this assumption?)

According to Wikipedia, a fact is "something that is the case, something that actually exists, or something that can be verified according to an established standard of evaluation." It goes on to say, "Just as in philosophy, the scientific concept of fact is central to fundamental questions regarding the nature, methods, scope and validity of scientific reasoning. In the most basic sense, a scientific fact is an objective and verifiable observation."

Evolution is a fact in both cases; generally and scientifically. It is the case. It exists. It can be verified. We have mountains of evidence to support it.

The logic isn't too different from that of gravity. Wikipedia says, "...it is a fact that an apple dropped on earth has been observed to fall towards the center of the planet, and the theories commonly used to describe and explain this behaviour are Newton's theory of universal gravitation (see also gravitation), and general relativity."

Likewise, it is a fact that a process (evolution) occurs that results in heritable changes in a population spread over many generations. The theory commonly used to describe and explain this is the theory of evolution, which includes Darwinian theory.

I call evolution a fact because it is...but also because calling it a theory leads to statements like "it's just a theory."

3 comments:

Zach Miller said...

If it's 32 degrees outside (as it is right now), you can't argue that it's NOT 32 degrees outside. The thermometer says 32 degrees. That's a fact. Likewise, evolution is a fact. There are various theories to explain the processes by which evolution occurs, but ultimately evolution...that is, genetic change over time...is a fact. It happens and can't be disputed.

Jerry D. Harris said...

He supports evolution, but claimed that the fact that something is happening doesn't make it a fact.

Hunh...?!? That statement wouldn't make any sense even if it made sense at all. Seriously, if it is happening, how on Earth can it reasonably be denied?!? Unless the denialist wants to reject all of reality (which occasional philosophers have tried to do...), but that's not really a reasonable perspective, and certainly not one that will enable one to be productive. On the other hand, someone's refusal to acknowledge that something may be happening is another matter, but that doesn't alter that the thing is happening. "J" may be laboring under the misconception that "facts" (e.g., reality) are transient, ephemeral entities that are dependent on human perspective. Perhaps more thought needs to be devoted to that notion.

More to the point, life of the past is different than life of today. Anyone that denies that is oblivious to reality: the fossil record contradicts that idea. Evolution, defined simply as "change through time," therefore has happened. Ergo, evolution is a fact, period, end of story. Now, the mechanism(s) by which that change may have happened might not be so readily obvious, and indeed there has been and still is much research into clarifying how that change occurred. This most emphatically IS NOT the same thing as saying that the change did not occur!!! No one (no one reasonable, that is) denies that life has changed through time -- no one denies that evolution is a fact. There's simply no universally agreed-upon explanation for the mechanisms that induce said change -- at least, none that operate universally -- lots of hypotheses, and even some theories (see later), but only a few that pretty much everyone accepts.

she argued that evolution cannot be proven to be an ultimate truth. (But what can? Can't we even argue our own non-existence under this assumption?)

For the latter, one again delves into the realm of philosophy, on which I'm not remotely qualified to answer. However, for the former, this person seems to be laboring under the (unfortunately common) misconception that science is about "finding truth." That is simply not correct (though you and she are correct that, in some respects, it does depend on what one defines as "truth"). Science is, and ever has been, only about finding testable, falsifiable explanations for various phenomena. No scientist worth his/her salt should ever say that something is "proven," though of course the public and the media continually make this small yet huge mistake of saying "scientists have proven this" or "scientists today proved that," etc. Scientists may continue to find support for a hypothesis -- and if, over a long period of time and after a large number of researchers have worked on it and produced support for it, it is elevated to the level of theory -- but they can never (and never claim to!) "prove" it, simply because we cannot examine/test it universally...there may always be some conditions somewhere/somewhere that were different and thus produce different outcomes. Personally, I think that this is where a lot of the wholly imaginary issue between science and "faith" comes in -- many people, for whatever psychological reasons, are uncomfortable with the lack of concreteness that comes with having to accept that there are unknowns out there, and that humans simply have not (yet) encompassed everything. "Faith" eliminates that and gives a person greater comfort and, shall we say, solidity. Unfortunately, since it often posits nonscientifice tenets (i.e., things that are not testable), it also necessarily leads to misconceptions about what science is and how it works.

I call evolution a fact because it is...but also because calling it a theory leads to statements like "it's just a theory."

Evolution is a fact; how evolution occurred is the subject of evolutionary theory (and evolutionary hypothesis). There's nothing wrong, or erroneous, in talking about evolutionary theory -- this too exists (!). The issue here is (again) how the word "theory" has become corrupted and incorrectly interpreted by the public and media. To the latter, "theory" and "hypothesis" (on the rare occasions where that word is actually known or used) are synonymous. As Isaac Asimov put it (paraphrased), "[people] make it sound as though a ‘theory’ is something you dreamt up after being drunk all night.” Of course, scientists do not use the term nearly so lightly -- the word "theory" applies only to something that has massive amounts of support and little or nothing contradictory. Something only attains that state after decades, sometimes centuries, of research by innumerable people, coming at it from many different angles, and all arriving at the same conclusion. To dismiss such a thing with a proverbial wave of the hand ("It's just a theory...") demonstrates a profound ignorance (and, dare I say, a severe deficiency in one's educational background somewhere...!). Not that I'm trying to put your friends down in any way -- I deal with this all the time in my own classes, and in fact deal with this whole "theory" thing on the first day. It's abysmally commonplace, and it's kind of funny, really, that such a small semantic issue has such tremendous ramifications (in re people trying to get nonscientific ideas, like creationism, elevated to the same "level" as a "theory"). Someone once bemoaned "Language is a stupid form of communication," and I'm forced to agree.

Amanda said...

"Unless the denialist wants to reject all of reality (which occasional philosophers have tried to do...), but that's not really a reasonable perspective, and certainly not one that will enable one to be productive."

And there's the rub...J's a philosophy guy (it's probably going to end up being his major). So, in philosophical terms, he's not wrong. However, you're right that it's not a productive perspective. We live in a world that operates under certain ideas(that we exist...that we can know things). In that world, evolution is a fact. Outside of that world, well, there's room for anything at all...unicorns, gods, marshmallow clouds.

"Not that I'm trying to put your friends down in any way..."

Of course not. I didn't take this that way and I hope they wouldn't either. They, of all people, understand the importance of having an opinion and arguing it openly. I love them very much...very proud to be sharing my life with them...even if we don't agree on everything (or anything).