jump to navigation

Emergence: Mystical Science? February 26, 2009

Posted by C. Steves in Nuts and Bolts.
2 comments
How do the complex interactions of an ant colony arise? Perhaps it's an example of weak emergence...

How do the complex interactions of an ant colony arise? Perhaps it's an example of weak emergence...

To ancient humans, the sight and sound of lightning and thunder must have been a baffling site to see. For thousands of years, I’m sure that humans would cower and shake like dogs while waiting out a thunderstorm. But the ancient Greeks were not satisfied with not understanding this meteorological phenomenon, and decided to attribute it to the expression of anger and discontentment of the god Zeus. They created a theory that attempted to explain a system they did not understand, an un-testable, un-falsifiable theory that could only hope to provide an explanation for these mind-boggling occurrences. This may very well be an early example of emergent theory.

(more…)

Formatting Wizardry (Off Topic) February 6, 2009

Posted by Greg in Nuts and Bolts.
2 comments

This doesn’t really have anything to do with philosophy, but Tony asked me how I do fancy formatting in my comments, so I figured I’d make a post about it instead of hiding it in a comment.

WordPress seems to support most of the standard HTML tags: <b>foo</b> for bold, <i>bar</i> for italics, <blockquote>baz</blockquote> for

block quotes

and so forth. A basic HTML reference might be handy here, or you can go to the “new post” page, press all the buttons (the buttons with text, not the “upload/insert” buttons), see what code it generates, and then just copy and paste that into your comment. This second method also has the advantage of letting you preview what your comment will look like.

Feel free to practice formatting in the comments to this post.

Underdetermination January 26, 2009

Posted by ebrister in Nuts and Bolts.
Tags: , ,
add a comment

 
We read an excerpt from Duhem’s The Aim and Structure of Physical Theory (1906) which introduced the notion of underdetermination of theory by evidence. The underdetermination thesis holds that individual statements cannot be empirically confirmed or disconfirmed by a single observation. This thesis upholds holism: that our theories are composed of collections of statements which are evaluated as a whole. Disconfirming evidence can be dealt with by making any number of changes to this collection of statements.

Duhem writes:

In sum, the physicist can never subject an isolated hypothesis to experimental test, but only a whole group of hypotheses; when the experiment is in disagreement with his predictions, what he learns is that at least one of the hypotheses constituting this group is unacceptable and ought to be modified; but the experiment does not designate which one should be changed.

This challenges two common beliefs about how science works.

1. We cannot give a complete logical reconstruction of scientific reasoning which makes a conclusion seem to have been compelled by evidence. This is obviously the case for induction from evidence because it’s possible to generalize from a limited set of observations in any number of ways. But it’s also true for deduction; say, along Popper’s lines. Due to underdetermination, we can’t make a conjecture, deduce the results we ought to see, and then know for sure which part of the theory has been falsified when the deduced prediction is disconfirmed.

2. If we have two theories that are empirically equivalent except for giving different predictions as to the result of a crucial experiment, then running that experiment ought to give us the ability to choose between them. However, the problem is that this assumes that there is no overlooked alternative theory–that the two we are choosing between are the only two possible explanatory theories. This is why Duhem says:

Unlike the reduction to absurdity employed by geometers, experimental contradiction does not have the power to transform a physical hypothesis into an indisputable truth; in order to confer this power on it, it would be necessary to enumerate completely the various hypotheses;…but the physicist is never sure to have exhausted all the imaginable assumptions.

 

© Kenneth Spring, Microscopy Resource Center

The class’s opinion last week seemed to be that understanding underdetermination was straightforward. I would like to point out, though, that the implications of the thesis are far-reaching and still of contemporary interest. For instance, here is the program for a conference this March on underdetermination.

Welcome to Philosophy 443 November 20, 2008

Posted by ebrister in Nuts and Bolts.
add a comment

This blog will host informative and speculative writing by students in a Philosophy of Science class at the Rochester Institute of Technology in the winter quarter 2008-09.

My previous student-authored website is a glossary of concepts related to the work of W.V.O. Quine. This blog format should allow simpler editing and more creative posts.