Wednesday, September 27, 2006

Necessary and sufficient

Although I like to pretend to be one on TV, I am by no means a practiced logician. However, I cherish the bits and pieces that I've learned, and one of those is that any position has what is called "necessary and sufficient" conditions to be accepted or rejected. In a nutshell, what this means is that one does not need to know "all of the evidence" before arriving at a conclusion about a subject. One merely needs to know, with confidence, certain points.

For example, many will argue that when one must know all about the formative years of a criminal to adequately render judgement. It is absolutely false; all that is necessary is to demonstrate that a crime was committed by that man while of sound mind and without provocation. We need not go into how his clothes were stolen when he was 11 while skinny-dipping.

In a similar vein, evolutionists might argue that one must understand all the complexities of radioisotope dating before judging its effectiveness. Again, horsefeathers; all that is necessary is to view a tree growing through ten layers of rock spanning (according to the method) tens or hundreds of millions of years. If trees do not live in rocks, or for millions of years, we must admit some weakness in radioisotope dating. We do not need to specify what it is, or suggest an alternative.

All too often, we get bogged down in the infinite details of a situation, to the point that we fail to discover what is necessary and sufficient. Let's stop buying "big mud tires" and instead walk around the marsh.

12 comments:

Mercy Now said...

Bubba, I'm sorry but I don't buy your logic because I really don't know who you are prior to running into your blog. I would only consider your points valid if I know of your history from when you were born.

I do this when I go buy groceries because in addition to looking at the produce, I have to ask the stock clerk where it came from, when it was harvested, and how long of a journey it traveled.

I was only being sarcastic, of course.

Anonymous said...

Your second example is indeed a good example of a logical fallacy. Since the position of mainstream geology for the past 150 years on such structures has been that the enveloping layers were laid down very rapidly, not over millions of years as you portray them as claiming, the name of this fallacy is "straw man."

Bike Bubba said...

No straw man, skeeter, but rather a case where radioisotope dating tells us that the lower layers are tens or hundreds of millions of years older.

You're right that standard geologic theory (and basic common sense) would admit that the rocks are of similar age. However, another standard geological theory is that of the efficacy of radioisotope dating, and we have a very interesting contradiction here. At least one standard theory must be cast into doubt here.

Anonymous said...

Show me the goods, Bert. I want citation for a mainstream geology paper, preferably several, that asserts via radioisotope dating that the various layers enveloping an upright fossil tree have ages that differ from each other on the order of tens or hundreds of millions of years. If you've got that, fine, then I'll want to see the peer review to see whether the papers stood muster. If they did, this would demonstrate that the position you are arguing against is actually a position held by your opponent. If no such paper exists, or if it does but was subsequently refuted, you've got a straw man by definition.

Bike Bubba said...

Joe, the straw man argument is an attack on a different argument than the opposition's weakest argument, and has nothing to do with peer review. Appealing to a lack of "peer reviewed" papers is the logical fallacy called "appeal to authority." Just like Darwin, those at "talkorigins" seem to have some serious problems with basic logic, as Philip Johnson made aboundantly clear in "Darwin on Trial."

And the trees? Yellowstone's Petrified Forest, and I also believe there are sites in Wales with the same phenomenon.

Anonymous said...

I guess then we disagree on the definition of a straw man. I always thought that it was presenting an easily-refuted position as if it is the oppostion's position, when it really isn't. Whether or not we agree to call what I just described a "straw man" or something else, I hope you agree that doing it is something to be avoided. Semantics aside, then, what I am asking you to do is to demonstrate that the position you are refuting actually exists.

I don't care whether you agree with the mainstream position, but I do care that you represent it accurately. My request for peer review, then, was not an attempt to demonstrate that the mainstream position was correct, it was an attempt to demonstrate that the mainstream position is not what you said it was. I was appealing to authority--the body of peer-reviewed literature is the authority on what the mainstream geological postion is. Whether this position is correct or not is a completely different question.

In a way, this whole episode refutes the point of your original post. Sure, you may not need to know "all the evidence" to refute a position, but if you haven't done the due diligence necessary to confirm that the position you are refuting is one the opposition actually holds, what good does it do you to refute it?

Bike Bubba said...

Joe, you're way off topic. Will comment on the insane allegiance to peer review, though.

Bike Bubba said...

Here is a link to an article about a tree crossing layers in Nova Scotia.

http://www.icr.org/article/445/

So no, there is no straw man here, nor is there a failure to do due diligence.

Anonymous said...

I don't see how I'm off topic. You gave an example of an argument that you could easily refute. In my comments I expressed doubt that the argument you were refuting is actually held by the opposition. I even tied my comments to the overall message of your original post.

I don't see at all how the way that I was attempting to use peer review can be called, "insane allegiance." I have treated you with respect even though we disagree and I don't think it's too much to expect the same from you. If you would prefer that I no longer comment on your blog, though, I will honor that.

Bike Bubba said...

Joe, see the newest post for why insisting on peer review is not only a fallacious appeal to authority, it also doesn't clarify the science once the "scientists" have closed ranks around a certain idea.

And see the link. You asked for evidence, you got it. ICR also has articles about the Yellowstone formations.

Anonymous said...

Bert,

You keep treating me like I'm discussing the veracity of the mainstream position, when I'm really discussing the content of the mainstream position. I don't see any point is discussing whether it is true or not because we have both made up our minds. On the other hand, I was hoping that you might benefit from realizing that the opposing view is more robust than the caricature you've been taught. I know I've benefitted from become more aware of the young-earth position. Even when I don't agree with it it helps me recognize which of my own arguments are strong and which are weak, and which of the young-earth view's arguments are strong and which are weak. You'll never discover these sorts of things if you only read stuff from AIG and ICR.

The link you gave is not the evidence I was looking for. You are answering questions I'm not asking and ignoring the one I am asking. The references in the article are almost entirely to ICR or similar publications, not to mainstream journals, so it doesn't help much in demonstrating that the position you refuted in your original post is actually what mainstream geologists believe. In contrast, this link has references to creationist publications when it describes their position, and references to mainstream publications when it describes that position. Regardless of which article you end up agreeing with, you have to see that the one I linked to provides better evidence of what the mainstream position actually is.

Your other post on peer review actually supports me in this, since one of the things it argues that the process tends to gravitate towards a consensus and punish dissent. That is almost certainly a bad thing, as you suggest, but it sure does make the body of peer reviewed publications a good authority on what the consensus is!

Bike Bubba said...

Joe, I don't believe I need to concede either claim. For starters, citing "talkorigins" and Don Lindsay is actually quite inferior to citing Lyell and others. Hyperlinks to one's own site don't make the case.

Moreover, consensus among prominent evolutionists means that, well, 100 years of keeping the other team off the playing field means you score all the points. It's not exactly meaningful.