In the movie Inception, the characters thrust themselves into the realm of the dream world in order to achieve certain goals. Since the dream world can often seem identical to the real world, a totem is used to distinguish between the two. A totem can be any device that a character is familiar with and is able to predict its behavior. For example, Dominick Cobb (played by Leonardo DiCaprio) keeps a spinning top with him knowing that, were he to ever spin it in the dream world, it would never stop spinning.
This inherent question of whether or not the world we experience is real or an illusion is a deep-seated one going as far back as Descartes’ evil demon theory. Once one begins the task of deciding what is real and what is not, a problem quickly emerges. Philosopher Roderick Chisholm explains:
To know whether things really are as they seem to be, we must have a procedure for distinguishing appearances that are true from appearances that are false. But to know whether our procedures is a good procedure, we have to know whether it really succeeds in distinguishing appearances that are true from appearances that are false. And we cannot know whether it does really succeed unless we already know which appearances are true and which ones are false. And so we are caught in a circle.
In other words, how can I know anything unless I know how I know it? But, then again, how can I know how I know anything unless I know something first? Chicken or the egg? This is the problem of the criterion. And no one can truly begin to think and shape his worldview until one addresses this problem.
There are three essential types of people who give responses to the problem of the criterion. First, there is the skeptic who says, “You cannot answer the first question without answering the second question. But you cannot answer the second question without answering the first question. Therefore, there is no way to decide!” A person can hold to this position if they so choose but, in order to live consistently with this view, she can never say that she knows anything – including what she just ate for breakfast, how much money is in her bank account, or whether her husband is cheating on her. This kind of far-reaching uncertainty is a very difficult position to hold for anyone who is intellectually honest.
Second, there is the methodist who says, “To answer the question of what comes first in the problem of the criterion, you must always know how you know before you can know anything!” The problem with this view is that the question of how you know can always be asked. So, for example, a methodist can say, “I know that A because B.” But then someone can ask, “How do you know that?” The methodist responds, “I know that because C… and I know that because D, E, and F.” Very quickly the methodist has slipped into an infinite regress from which he cannot recover since his own criterion will always come back to haunt him.
Finally, there is the particularist who simply says, “There are certain things that I just know without having to know how I know them.” For example, how do you know that 2 + 2 = 4? How do you know that your thoughts are your own and not someone else’s? How did Descartes know that he was actually thinking and having doubts in the first place? These are questions that cannot be answered by using the five senses or appealing to some other kind of criterion first. These kinds of examples are known purely by your direct awareness. The particularist fully admits that he has no explanation for how human beings know things by direct awareness but he says that’s not necessary. We should accept those things (what philosophers call epistemically basic beliefs) as our foundational knowledge from which we can then answer the second question: how you know?
As a personal aside: I am a particularist because that is what makes most sense to me. As one who oftentimes adheres to an Ockham’s Razor of sorts to decide between several competing ideas, I hold to the particularist view for two reasons. First, the other two positions are too problematic as I’ve briefly shown. And second, in my experience of reality, one must begin with the tangible in order to address the procedure. Think of the process of evolution. Evolutionists cannot say, “First there was evolution.” No, first there was the cell. And likewise, in the problem of the criterion, there must first be knowledge in order for there to be a process of knowing.
As I’ve previously mentioned, one cannot truly begin to shape his worldview unless he wrestles with this problem. Therefore, I will end this post with a question: Considering the problem of the criterion, which type of person are you?
 Roderick M. Chisholm, Foundation of Knowing (Minneapolis: University of Minnesota Press, 1982), 62.
 These 3 types are presented more fully in the book entitled The Problem of the Criterion by Roderick M. Chisholm.
 Not to be confused with a follower of John Wesley’s teachings.
 Of which I find unsound for too many reasons to list in this post.