You hear it all the time. “Stanford students may be book smart, but they don’t have any common sense.” This is an especially powerful claim to me because, well, I will freely admit, I am a Stanford student, and I also happen to lack common sense.

I can never really get an answer, though, when I ask what not having common sense means. Common sense is a nebulous term, associating many disparate ideas under its collective umbrella. Regardless, it seems we seem to lack whatever definition you choose.

Seeking a complete definition, although it seems contrary to the nature of common sense to find it in a book, I looked it up in the dictionary and obtained the following: a sound and prudent sense of things common to humanity.

But what does this mean? Sound and prudent? A sense of things? Common to humanity? Says who? What humanity?

Maybe a more informative approach to defining common sense is to present for you the times which others have scolded me for lacking it. From these three examples, maybe we can devise a better working definition:

1.) I recently attempted to order 800 hotdogs for a barbecue of 400 people. It is “common sense” that 800 hotdogs are entirely too much for this variety of gathering. Add to that, not only are 400 people not going to eat 800 hotdogs, but I would not be able to purchase 800 hotdogs from Safeway, which I was trying to do.

2.) I slept next to a radiator on a cold night the other day. I woke up with a burn across my back. It is “common sense” that radiators burn skin.

3.) I tried to argue that leaving out a bag of candy on your porch for Halloween would be fine. But it’s just “common sense” that kids aren’t going to just take one.

Anything involving natural phenomena, bodily responses and social phenomena that I should have been aware of, I will admit fall rightfully under “common sense.” These truths are, in many respects, inherent. Based on the collective experiences of mankind, they are known to avoid hurt and other maladies.

But what about the third? While here, its application seems similar to the other two, it is instructive to think about what applying common sense is really saying. Ultimately, “common sense” used in this context means nothing more than “I’m taking this for granted.” It is a way to start in the middle of an argument – to assume a shared knowledge-base of primitive, inarguably true premises.

And while this may make sense in the context of safety brochures about radiators, from a philosophical point of view it is horrifying. Can we not get back to the days when Descartes was able to doubt everything except his very existence? When he systematically sought out those things which were inherently true, and concluded that they were dreadfully few in number (namely, there was only one)?

Common sense seems to revolve around the idea of “obvious.” But I hate “obvious.” To quote Einstein here, and I rarely do this because people quote Einstein too much, “Common sense is the collection of prejudices acquired by age eighteen.” “Obvious” is often nothing more than the status quo. The best discoveries are not the obvious ones, but those that are counterintuitive, that force us to reconsider everything we previously held self-evidently true.

To go around trumpeting “common sense,” at least in the third sense, is to go around supporting the way things are and saying it is the way things always will be.

You know what? I am proud to lack common sense. While certain aspects of my common-senselessness may indeed result in physical harm or social embarrassment, these are byproducts of a generalized skepticism, one which I believe is healthy and just.

The next time you are berated for lacking common sense, first, check for burn marks. If you don’t see any, however, it may just be that you are questioning something that should be questioned.