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On Roderick Chisholm

Matthew Davidson briefly defines an important analytical thinker.

Roderick M. Chisholm (1916-1999) was one of the most important philosophers of the 20th century. His influence on epistemology (the theory of knowledge) and metaphysics cannot be understated: indeed, it is difficult to conceive of what these fields would be like today without the impact of Chisholm. Were there a Nobel Prize in philosophy, Chisholm surely would have won it. But who was he?

Chisholm graduated from Brown University in 1938 and completed his PhD at Harvard in 1942. After finishing his dissertation, ‘The Basic Propositions of the Theory of Knowledge’, he entered the U.S. Army. After a short stint in infantry training, he received training in clinical psychology and worked at army hospitals in the southern United States.

After being discharged in 1946, Chisholm returned to Brown University, where he taught until his death in 1999. During this time, he published hundreds of articles, and many books, including Perceiving (1957), three very different editions of Theory of Knowledge (1966, 1977, 1988), Person and Object (1976), The First Person (1981) and A Realistic Theory of Categories (1996).

The Philosophy

Chisholm is perhaps best known for his attempts to bring clarity and rigor to philosophical thought. Philosophical analysis for Chisholm involved very precise definitions of key concepts. Consequently, the humorous Philosophical Lexicon (see philosophicallexicon.com) has the following entry:

“[to] chisholm, v. To make repeated small alterations in a definition or example. “He started with definition (d.8) and kept chisholming away at it until he ended up with (d.8’’’’’’’’).”

Indeed the verb ‘to chisholm’ really has become quite widely used, appearing in sentences like “This idea needs some chisholming” or “This claim might make sense, but it would take much chisholming to see that it does.” Another associated well-known term is a ‘Chisholm-style definition’. Many times at conferences I’ve heard people ask for a Chisholm-style definition of some concept they found obscure.

For an example of the sorts of definitions Chisholm himself gave, here is his definition of ‘possible world’:

“‘W is a world’ =df [ie, means by definition that – Ed] W is a state of affairs; for every state of affairs p, either W logically implies p or W logically implies the negation of p; and there is no state of affairs q such that W logically implies both q and the negation of q.”

Chisholm typically would give very precise definitions like the one above, and then go on to generate further complex definitions from the original. For instance, he has a precise definition of ‘state of affairs’, a term which appears in the above definition of a possible world.

Roderick Chisholm put forth and defended many deep and important philosophical theses. His reasoning always was intricate, and it is hard to summarize his thinking in any short space, but let me briefly mention two of his philosophical theses. First, he defended a view of knowledge whereby to know that some proposition p is true means that one must be able to discern that in believing p one is not violating any obligations one has with respect to forming beliefs appropriately. He was perhaps the most important contemporary? defender of this sort of view, called deontologist internalism.

Second, in metaphysics, he held the view that ordinary objects (tables, chairs, etc.) are ‘logical fictions’, and that what exists “in the strict and philosophical sense” are parcels of matter. Parcels of matter cannot lose parts and continue to exist as the same things, according to Chisholm. But what we think of as ordinary objects are gaining and losing parts all the time, he noted. Some molecules that once composed the table in front of me no longer do so. They have been chipped off, and the table worn away with time. The same holds for human bodies. They gain and lose parts all the time, and thus for Chisholm, human bodies don’t persist through time “in the strict and philosophical sense.” But persons – whatever they are – do persist through changes in the matter that composes a body. Therefore, he concluded, persons are not identical with their bodies, nor with any part of the body that can undergo change. At one point in his career, he concluded that human persons must be tiny (ie unextended or point-like) substances that are spatially located, probably inside the brain. Because they are unextended, these ‘Chisholm objects’ have no parts, and thus cannot gain and lose parts.

The Man

Former colleagues and students of Chisholm have many stories about this remarkable philosopher. His long-time colleague Ernest Sosa, the Romeo Elton Professor of Natural Theology and Professor of Philosophy at Brown University, recalls the following:

“Soon after I arrived at Brown, we were on the phone many times a week, sometimes several times a day, trading counterexamples and revised analyses. He was mostly the source of the analyses and I mostly the source of the examples, but we had a lot of fun going back and forth. This went on for decades, from the mid –sixties until well into the eighties at least… Very early he was using computers, too, though at that time what we had available at Brown was just a line editor, where one line would appear on the screen at a time. He got used to that, though, and would never upgrade to full page editing. He was so full of philosophical ideas up to very late in life that he did not want to take the time to learn all the newfangled systems, and preferred to stick to the tried and true. I think he liked to mull over ideas at great length and was satisfied with a line at a time.”

One of his last PhD students, Dean Zimmerman, who is now an Associate Professor of Philosophy at Rutgers, remembers:

“I’ve often repeated his advice to me in our first conversation about my dissertation. We were taking a little walk in the neighborhood of his house out in Barrington and he said, “The most important thing about a dissertation… (pause) is that you get it DONE.” That’s a very encouraging thing to hear from your advisor, right off the bat – you hear these horror stories of directors who keep adding problems you should address, and more literature you should interact with, and saying things like “it should be your magnum opus” (what a silly idea!)… I think a lot of us found it very charming when, in seminar, he would refer to us by last name alone; you know, “Zimmerman’s objection to my proposal seems to presuppose that...” You hear that, and you suddenly feel like you’re a serious person; only serious people get called by their last names in that way!… The thing that most impressed me about him, as it has so many others, was his willingness, indeed eagerness, to have you prove him wrong about something. It wouldn’t have been so impressive if he weren’t so ambitious and hopeful, developing theories that he’d really like to see turn out to be true or at least adequate to the facts and more likely than alternatives. He combined confidence in his own abilities with the desire to get it right and extreme openness to the help and criticisms of others – a kind of humility before the truth, a willingness to yield to the truth, at the expense of one’s pet theory, and to be grateful to critics for showing its inadequacies. A lot of his students have been inspired by that combination of attitudes, and have hoped to achieve some pale imitation of it, anyhow, in their own intellectual lives. However imperfectly we’ve managed it, the result has still been a lot of good for the profession as a whole, a lot more virtue spread around in philosophy departments than there would have been without his example.”

James Van Cleve, Professor of Philosophy at Brown University, was also influenced greatly by Chisholm. He recalls:

“I joined the Brown faculty as a young assistant professor in the 1970s and religiously attended Chisholm’s seminars for many years. I knew at the time that I was witnessing an extraordinary man, but just how extraordinary has become clearer with each passing year. One thing that especially impressed me about Chisholm’s style of teaching is that he never answered a question without making sure that everyone understood what question had been asked. He would restate questions that were clumsily or confusingly formulated, interrogate the questioner if necessary, and point out just what hung on the answer. That may sound like a small matter, but it is not. How many times have I heard a speaker at a professional meeting launch into an answer to a question as though the questioner, the speaker, and the audience all knew what the question was and what turned on it – when in fact this was not the case! My efforts to follow Chisholm’s model in my own teaching have made me acutely aware of how rare were his gifts.”

The Legacy

When Chisholm died in 1999, it was a great blow to philosophy. He was one of the founders of contemporary philosophy, in the same sort of way that Einstein and Feynman were founders of contemporary physics. His influence is ubiquitous. One sees ‘Chisholm-style definitions’ frequently in contemporary philosophical literature. Young American philosophers continue to learn to do philosophy by reading Chisholm. Even if one does not agree with his views, his rigor and clarity stand as models for how one should engage in philosophical thinking.

Philosophy today places a premium on being precise in what questions one is asking (and many of the questions being asked today are the result of Chisholm’s work), and being clear in the concepts one is employing. This striving for rigor is perhaps the most important bequest of 20th century philosophy. No one contributed more in this regard than did Roderick Chisholm.

© Dr Matthew Davidson 2009

Matthew Davidson is an Associate Profesor of Philosophy at California State University, San Bernardino.

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