No. 2891: SPECIFICS AND GENERALITIES

by Andrew Boyd

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Today, what exactly is that? The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

We all know what a table is. Or do we?

What is it that makes a table a table? Is it because it has four legs? No, four's common, but tables can be made with any number of legs or even using a pedestal. Is it because the legs support a rectangular surface? No, tables can be circular, oval, triangular, or, as I've had a chance to observe, shaped like the state of Texas. Perhaps it's because we eat at tables. No again. Tables can be used for bookwork, to hold lamps, or as a place to set coffee and large picture books. When we look at a table, what exactly is it that makes it a table and not say, a craftsman's workbench?

table texas photo

The bigger question is how we connect instances of something with their generalization — the table right here in front of me with the general concept of "table." It's a problem philosophers have wrestled with for millennia. Plato proposed an ethereal world of ideal forms that allowed us to recognize things in the material world. To Plato, all the different tables we see are shadows of an ideal table that exists in a Platonic realm. We're able to recognize the many types of tables because they share some "tableness" with the ideal table.

Few today adhere to what's known as Plato's Theory of Forms. Alternative explanations abound, but one, championed by seventeenth century philosopher John Locke, is the basis for many of them. Locke argued that as we grow from childhood we encounter many different objects. Some, we are told, are tables. Over time our brains generalize these specific instances to arrive at the concept "table." Thus, it's through "EXPERIENCE" that we learn what is and what isn't a table.

I can't possibly distill the intricacies of such a long debated question, nor, for that matter, am I a philosopher by training. But as a teacher I've learned a lot from the following thought experiment. How would you describe a cat to a visitor from another planet?—Perhaps furry, with four legs, a tail, and whiskers. A dog then wanders by, and our visitor confidently, and incorrectly, proclaims, "cat." If on the other hand, we'd shown the visitor a dozen cats and said, "cat," and a dozen dogs and said, "dog," our visitor probably wouldn't have made the same mistake. Students aren't aliens, though most teachers will profess that at times it can seem that way. But like our alien, students learn more when a general concept emerges from examples than they do from nakedly abstract descriptions. When it comes to learning, Locke's emphasis on examples beats Plato's abstract realm hands down.

And it's not just examples, but practice. Which is why students past, present, and future will always get homework.

I'm Andy Boyd at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Notes and references:

"EXPERIENCE" is capitalized and in quotations because this is how Locke emphatically presented it in Book 2, Chapter 1 of An Essay Concerning Human Understanding.

Locke, J. An Essay Concerning Human Understanding. 1690. Many on-line versions are available. See, for example, http://john-locke.com/an-essay-concerning-humane-understanding/. Accessed June 18, 2013.

Theory of Forms. From the Wikipedia website: http://en.wikipedia.org/wiki/Theory_of_Forms. Accessed June 18, 2013.

Universals. From the website of the Internet Encyclopedia of Philosophy: http://www.iep.utm.edu/universa/. Accessed June 18, 2013.

The picture of the Texas table is by Thierry Amisse, who does fine French woodworking from his studio in Austin, Texas: http://thierryamisse.moonfruit.com/. The dog and cat pictures are from Wikimedia Commons.

This episode first aired on June 20, 2013.