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That’s Common Sense!


That’s Common Sense!

by Rick Pimentel

There are so many issues that people discuss with one another that have philosophical significance. Whether it is at the dinner table or at a restaurant or at a café or in the living room or on the phone, we all discuss issues that pertain to fundamental aspects of life that are directly or indirectly addressed by philosophy. These conversations touch upon, sometimes unintentionally, ideas that significantly impact our lives. For this reason, Philosophy New is launching a new feature area called the “Table Talk Series.” This series will examine “everyday ideas” and consider how philosophy can inform those discussion making philosophy more practical to our lives.

How many of us have participated in a conversation in which someone has stated in response to something that sounds profound, “That’s common sense!” A statement used as often and as convincingly as this seems to be important. Many of us use it and believe it. Defining common sense can be difficult because there exists a simple, popular meaning and a more complex, philosophical meaning. According to Dr. Jonathan Dolhenty, the late co-radical_academy_logo founder of the Center for Applied Philosophy, common sense is the “the conglomeration of generally held opinions and beliefs, more or less well founded, more or less mixed up with error and prejudice, which make up the voice of the community -- what everybody knows.” Many would read this and say, “That’s common sense!” Despite the fact that some would not use all these words, it is safe to assume that many would agree with this popular and simple definition. However, does it fully describe common sense? This is where philosophy steps in. The same Dr. Dolhenty offered a philosophical definition for common sense when he stated the following:

Common sense refers to the spontaneous activity of the intellect, the way in which it operates of its own native vigor before it has been given any special training. It implies man's native capacity to know the most fundamental aspects of reality, in particular, the existence of things (including our own existence), the first principles of being (identity, noncontradiction, and excluded middle), and secondary principles which flow immediately from the self-evident principles (causality, sufficient reason, etc.).

This definition is certainly more complicated but does this definition, in conjunction with the popular definition, tell us anything about common sense? Thankfully, it does. First of all, the word “common” is important. It implies that all people have the capacity to have this sense. Second, the point that common sense is “more or less well founded” is significant because people possess common sense independent of any specialized knowledge or training (though not prior to experience; common sense is decidedly a posteriori). This is arguably the reason why common sense is appealed to by many people; it is not specialized. Lastly, common sense does not apply to specialized knowledge. Put differently, common sense is used to evaluate common scenarios. (That should be common sense.) If it can be possessed independent of any specialized knowledge or training, then it is obvious that common sense does not apply to specialized knowledge. So, if you hear one rocket scientist telling another rocket scientist at the water cooler, “The ambient temperature of the combustion chamber is inversely proportional to the fluid mass of the rocket propellant” and the second rocket scientist laughs and says, “That’s common sense!”, then you can step in and say, “I am sorry but that is not common sense.” (Keep in mind that I do not know if rocket scientists would ever have this conversation or if rocket propellant has fluid mass; it was “fueled” by my imagination). It is not common sense because the knowledge that these two scientists possess is specialized.

Dr. Dolhenty’s philosophical definition for common sense emphasizes the fundamental aspects of reality (e.g. the existence of things, laws of logic and being, and principles of causality and sufficient reason). Although the popular definition is good, it does not exhaustively describe common sense. The popular definition indicates that there exist pieces of knowledge that are obvious (i.e. common sense). But, the philosophical definition points out the exact components of common sense. When asked about common sense, the average person will not define common sense as knowledge of the fundamental aspects of reality as demonstrated by the laws of logic and being. This is not to say that the average person is stupid. It is probably because they may not know how to describe common sense in these words. For instance, if a philosopher describes the law of non-contradiction to the average person by stating, “No statement can be both true and not true in the same sense”, the average person will reply, “That’s common sense.” This person may not know how to put it into words, but they can certainly recognize when something is common sense. Why? Because common sense is knowledge that we all possess of the fundamental laws of logic and being. These are self-evident principles that need no proof. Mortimer Adler famously stated, “They are self-evident because the opposite is unthinkable.” It is here, where common sense finds its home. Although the philosophical aspect of common sense can seem complicated, it is really simple when you take time to examine it. Hopefully you can see that philosophy and table talk go hand in hand.

Is Philosophy Necessary?

In this piece, Craig Rood, a graduate student in philosophy at North Dakota State University opines about the value of philosophy in light of the University’s decision to close the Cardinal Muench Seminary. By closing the seminary, the philosophy department at NDSU will lose two of its professors due to lack of funding. Rood’s article raises some interesting questions about the role philosophy plays in the modern university with implications of questions the role the discipline plays in education in general. When looking to cut costs, administrators tend to gravitate towards the humanities as easy targets. Philosophy programs with their meager enrollments and long programs, tend not to fare well.

But the article also raises larger questions about the value of philosophy and the disciplines it engenders. Most philosophers I come in contact with are in the discipline because they love it and not only believe it’s valuable, but believe it’s essential to a well-equipped intellectual life. Root’s conclusion is that “human beings absolutely need a philosophy in order to live.” While this seems prima facie true, this doesn’t necessarily mean human beings need philosophy as the formal discipline to develop a philosophy of life.

Still, knowing even a little philosophy and spending some times in its core disciplines (particularly logic, epistemology, and ethics) can make all the difference in how one develops intellectually. A strong theme in existentialist thought is the distinction between being on the inside and the outside of an idea, a relationship, or an endeavor. The view from the outside may give one the impression the idea is irrational, confusing, useless, and meaningless. However being on the inside, one sees things very differently. This transition from out to in can only take place by an irrational leap and that leap is a hard boundary—a firewall—for many.

Philosophy is like that. From the outside, it seems pedantic and impractical. For those of us that have spent time on the inside however, we have come to learn that it is indispensible .

Epistemic Closure or Closed Epistemology?

I ran across this amusing article this evening. The title caught my attention. Typically when interdisciplinary terms find their way into popular speech acts, they retain some semblance of their original meaning. In this case, the term “epistemic closure” seems to have fathered a bastard child with the same name. As the author, Jaime Weinman, understands the term as it’s being used in the blogosphere, epistemic closure is “being unreceptive to facts that don’t fit into the pre-approved worldview.” Weinman even includes a nice Venn diagram to illustrate the difference between truth, belief, and knowledge. The term as used by epistemologists has nothing to do with being closed minded but with whether the justification of one argument transfers to another by implication.

Weinman capitalizes on the term to excoriate conservatives for their “myth creation” regarding certain political issues. This is unfortunate because epistemic closure as defined by epistemologists could actually inform Weinman’s analysis of the conservative movement. Nevertheless, if there really is a “great epistemic closure debate” occurring in 2010, epistemologists everyone should take up intellectual arms and seek to correct the term’s usage so things don’t get too far out of hand. I suggest the following.

1. If you see the term epistemic closure being used improperly in a blog or article, point the author to Steven Luper’s fine article at the SEP here. In this article, Luper defines epistemic closure as: If, while knowing p, S believes q because S knows that p entails q, then S knows q. Every author using the term should memorize and internalize this definition.

2. Ensure the author reads the debate between Dretske and Hawthorne in Contemporary Debates in Epistemology edited by Steup and Sosa. These essays are a good primer on the epistemic closure discussion and should correct any misuse of the term. Dretske argues that epistemic closure fails but this does not entail skepticism. He defines closure roughly as the idea that if S knows that P is true and knows that P implies Q, then, evidentially speaking, this is enough for S to know that Q is true. He makes a distinction between heavyweight and lightweight implications of a given proposition. Heavyweight implications are those implications that may form the metaphysical (philosophical) basis for certain facts to be true (cookies in the jar implies that there is a material world). Lightweight implications are those implications that are "nearer" to the fact in question (cookies in the jar implies that the jar is not empty). Evidence may transmit to the latter, but not to the former.

A typical believer--one who does not consider heavyweight implications--knows that she hands or sees cookies in a jar. She also knows that she's not a brain in a vat. But this is only true as long as she doesn't seriously consider heavyweight implications. As soon as she does, doubt is introduced and the epistemic context changes. When she considers whether she is a brain in a vat, she does not have enough evidence that she isn't (even if she uses the evidence that she sees cookies in a jar or has the experience of using her hands) and, under this epistemic context she doesn't know she isn't a brain in a vat. If this is true, then on closure, she doesn't know she has hands or that there are cookies in the jar.

Hawthorne demurs. In defending closure, he argues that if I believe that someone knows P and deduces Q from P, to say that he doesn't actually know Q isn't merely conversationally inappropriate. The natural thing to do would be say that he actually does know Q and so to deny that he does needs an explanation. It's not enough to say that he actually does and that the closure principle, like the claim I know I have a hand but imply that I might not by making the very claim, is not simply a matter of practical infelicities. If closure is wrong, there needs to be an explanation why it is so and Dretske cannot merely appeal to the fact that its denial is true but it may seem to have intuitive force only when it is brought to the attention of the believer.

The blogosphere needs to get its arms around this.

3. Ask for a retraction and apology from anyone improperly using the term. Closure is just too important to have it thrown around improperly and bloggers need to be called on the carpet for their infelicities.

Philosophers have worked too long and too hard on problems like epistemic closure to have terms commandeered while retaining none of the substance of the meaning of those terms. I’m only half joking.

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