Thursday, July 10, 2008

Quote: Fish and nets

Michael Shermer (in Why People Believe Weird Things) used this quote that struck a chord with me. The quote comes from Sir Arther Stanley Eddington's The Philosophy of Physical Science.
Let us suppose that an ichthyologist is exploring the life of the ocean. He casts a net into the water and brings up a fishy assortment. Surveying his catch, he proceeds in the usual manner of a scientist to systematize what it reveals. He arrives at two generalizations:

(1) No sea-creature is less than two inches long.
(2) All sea-creatures have gills.

In applying this analogy, the catch stands for the body of knowledge which constitutes physical science, and the net for the sensory and intellectual equipment which we use in obtaining it. The casting of the net corresponds to observations.

An onlooker may object that the first generalization is wrong. "There are plenty of sea-creatures under two inches long, only your net is not adapted to catch them." The ichthyologist dismisses this objection contemptuously. "Anything uncatchable by my net is ipso facto outside the scope of ichthyological knowledge, and is not part of the kingdom of fishes which has been defined as the theme of ichthyological knowledge. In short, what my net can't catch isn't fish.
Shermer was using this quote to say something about instrumental bias in science, but it struck me as being more relevant to the demarcation problem. The demarcation problem is the question: "What is and isn't science?" If we take the metaphorical ichthyologist's perspective, what you can't measure isn't science. What isn't science isn't real.

This quote resonated with me for a moment, as I thought, "I'll have to reconsider my thoughts on science in light of this!" But when I thought it over, I realized that it only confirmed my previous ideas, which is always a disappointment.

What are these previous ideas I speak of? First, I think it's possible for there to be real things which are nonscientific. I just don't think such things are likely to have any relevance to our lives, or that it is possible to know about them. Second, I also think there are scientific things that can't be measured. That is, they're scientific in principle, but not in practice. Therefore, nowhere must I take the absurd ichthyologist's perspective.

Any reactions to the quote, perhaps opposite or completely unrelated to my own?


Anonymous said...

I'm going to climb directly into my most recent related thoughts:

meaning in life

The scientific method requires methodological naturalism. If you take that to its ultimate conclusion, playing "fundamentalist empiricist", you end up at nihilism: there can be no such thing as meaning in life. There is no meaning.

Sure, you can pull some game-theory and argue for an emerging cooperative morality, but that still doesn't provide any real meaning. If you have a goal, "explore the universe", you can then figure out what moral codes (cooperation) would best accomplish that.

But you still have no reason for anyone to stick to that, no reason to not commit suicide... All of this does touch on the subjective experience of life. Does the subjective experience of meaning "exist"? That's kinda depends on your ontological perpectives, I think.

But I agree with most of your "previous ideas", they seem pretty good. The only clause that is problematic for me is "I just don't think such things are likely to have any relevance to our lives".

I do think the ichthyologist is making a mistake... first I'd suggest his net might improvable over time. But ok, this is a metaphor, let's assume it represents "godly science", the ultimate that science can achieve, millions of years hence.

Something similar to string theory? If we have a theory that can describe reality, but cannot be tested, it is not science. And it is not useful, as it has no predictive value -- having predictive value implies testability. If it is not useful, yes, it has no relevance to our lives.

But meaning in our lives is not "testable" (it is subjective). Arguably, it doesn't "exist". But it is definitely of relevance to us.

What about God? If we first chuck supernaturalism (which would be something "real" and hence testable and hence something we could pull into science, unless it destroys science completely by unpredictability of course: being governed by the "laws" in a deity's mind, thoughts that are inaccessible to us), there is still a question of some "meaning giver". Without supernaturalism, there's a number of paths by which we could consider "communication" with the meaning-giver. Christian tradition could suggest "God became man to communicate", even chucking supernaturalism. How was Jesus connected to God then though? Through subjective experience in the mind...

It pulls me back to a perspective where your subjective consciousness/mind is your meaning-giver. Some think it connects to an outside entity, some "own" it completely. "It's mine, completely natural, our concept of right and wrong evolved, our ability to reason about right and wrong evolved (evolutionarily taking a bite of the tree of knowledge of good and evil)." Some share it using a kind of democratic process (e.g. law).

The difference becomes one of semantics. And of course there are then "incorrect believes about the meaning-giver". E.g. beliefs in miracles that have nothing to do with meaning-giver, and rather just limited human interpretive ability and story-telling. (The source of that? Still the meaning giver. The famous non-theistic Christian, John Shelby Spong, also suggested "God is something inside you".)

I can continue babbling, but I've already written too long a "comment". ;)

miller said...

I agree that when we get to meaning, ethics, or morality, we must add another level of complication.

When I spoke of things that have no relevance to our lives, I was talking about real nonscientific things. And you're right, I was thinking in terms of "godly science" (not my favorite definition of science, but I felt it was appropriate here). Maybe string theory is an example, but it's a bad one, because I figure the point of an example is to simplify things. ;-)

I would not place meaning or ethics into the real nonscientific category. Not because I think they're scientific, but because I consider them to be important exceptions to my rule. If I had to, I would take the relevance of ethics and meaning to be an axiom. However, if there exists a "real" standard of ethics or a "true" purpose to life, its existence would be irrelevant. Also impossible, because that contradicts our axiom among other things.

For example, let us presume God exists, and has a "true" standard of ethics. The fact that God's standard is the "true" one is irrelevant to us. What is relevant is the fact that God endorses it, and we endorse God.

And speaking of God, God's category depends on God's definition. As a self-identified atheist, I don't feel I have a right to decide other people's definitions for them. But most definitions I would consider scientific in principle, but not in practice. Especially when it's all based on experience. Experience itself is usually scientific in principle but not in practice.

Anonymous said...

/me nods in agreement.

Ólafur Jens Sigurðsson said...

Hugo, giving meaning to something (like life) is a human term, so if you want to search for a meaning in life then you are basically saying that something or someone put us here and put meaning to our lives. The only difference between a stone in free space (no gravitation or EM waves around it to affect it) and a stone thrown by a human is that the latter has a meaning (it is being thrown somewhere by someone) and it got that meaning from the person which threw the stone.

So I would say that you can't apply the concept "meaning" to anything unless that meaning is applied in the first place by a sentient being.

Things that we say in our daily lives have a meaning in life, like say "the flies are here to feed the birds" are not really "meanings" in the sense that I am talking about it (and I don't think you mean that either), the flies are there and have a purpose but no meaning, the birds just use them as food source.

Great blog Miller by the way, just found it the other day and will be an avid reader (but perhaps not such common participant) in the future.