When we talk about things like knowledge and belief, we tend to use vertical-spatial metaphors: foundation; base; grounded; at the bottom. Wittgenstein’s spatial metaphors tend to subvert such vertical-spatial images. He’s fond of using the house as a metaphor for these epistemological concerns. Instead of the foundation holding up the rest of the house, he says “these foundation-walls are carried by the whole house” (248). Wittgenstein’s imagery follows from his desire to question continually the human impulse to speaks as if belief and certainty really were grounded, founded upon, based etc. For belief, he gives a stunning image that reorients this desire to ground, saying,
We believe, so to speak, that this great building exists, and then we see, now here, now there, one or another small corner of it. (276)
which is drawn to contrast with the notion that we build up our beliefs from some foundation, and upon these beliefs we pile more and more until we have some sort of certainty-orienting edifice. This image of Wittgenstein’s gives the lie to such a notion, though, in a remarkable way. When we’re fit to question them, our beliefs already exist. That is, there already exists “this great building”, our beliefs. The idea that we consciously build up our system of beliefs one piece at a time, always going by means of logical entailment from one to the other is shown false by a simple thought experiment. If someone asks you if you believe you’ve descended from great-great-great-grandparents; or if someone asks you if you believe you haven’t, say, descended from felines; or some such other strange-sounding—yet obviously true—notion, you would say, “Yes, I believe…”. Just by being human in a human society one’s larder of belief comes well-stocked. Such beliefs (e.g., “I believe I descended from great-great-great-grandparents
There is a reason why it seems like we have an infinite supply of beliefs about which we’ve never thought; and this reason also underlies Wittgenstein’s main point that beliefs actually resist vertical-spatial metaphors: We don’t acquire single beliefs—i.e., single propositions—but, rather, we acquire whole systems of beliefs, whole systems of propositions (141). Prefiguring the “great building” metaphor, Wittgenstein says, “Light dawns gradually over the whole” (141). A person cannot believe one belief in isolation, that is, exclusively. Even the simplest sort of belief, such as “I believe I live here” relies on other beliefs: the belief that my language itself makes sense; the belief that I haven’t fallen prey to a deceptive plot; etc. More well-developed beliefs rely on an even wider net of beliefs. The belief that the Cardinals will win the World Series relies on beliefs about the Cardinals’ personnel; beliefs about the game of baseball; beliefs about the efficacy of baseball’s officiating; beliefs about the fairness and uniformity of the game’s rules; and so on.
This picture of belief may seem like it could support a foundational-type notion of belief. But the picture does not if what one means by “foundational-type notion of belief” is that there will be a certain belief upon which all other beliefs rest. But this isn’t to say that there are no such things as well-founded beliefs. For example, when I say, “I believe I’m a human being”, I’m uttering a well-founded belief. Within my whole system of beliefs, this belief is heavily relied upon by many other beliefs. I have no beliefs that seem remotely to contradict this belief. It’s very firmly rooted within my system. As Wittgenstein says, a belief isn’t firmly rooted because it seems a priori true, but, “it is rather held fast by what lies around it” (144). It’s never occurred to me that I believe that I’m human, but as I write this, it’s as if a light shone upon this belief and exposed many other beliefs standing about it that could hardly fail me. Just as I believe I’m human, I also believe my name is Brian Payne; I believe I live in Santa Fe, NM; I believe I attended such and such a high school; and I believe that these are all normal human beliefs. But none of these beliefs ground another of them: They are all mutually dependent upon one another, like threads woven into a wall hanging. Certain threads could even be removed from the wall hanging and the picture would still be intelligible; but if too many were removed, the wall hanging would lose its coherence and it would cease to represent anything. However, no one thread is the most important thread, and no one thread serves as the foundation for the rest of them. Concerning beliefs we find that at the bottom of things there is, as it were, no bottom. That is, there is no foundation for well-founded beliefs (253).
This wall hanging is not a museum piece: It isn’t public. This isn’t to deny the notion of widely held beliefs; i.e., there are beliefs that are shared by many. Comparing “I believe” to “I know” best shows the idea at which I’m getting. If someone were to say, “I know there’s a God” one would have to ask how it is he knows. Does this person who knows there’s a God have a proof? Has he been privileged to divine revelation? Etc. But what could one say to the person who says, “I believe there’s a God”? Wittgenstein retorts, “If his opponents had asserted that one could not believe this and that, then he could have replied: ‘I believe it’” (520). A belief doesn’t pretend to assert a truth about a state of affairs. A belief asserts something about the believer, something about which the believer may be wrong; but the belief is not something that is open to public correction. (An utterance of the form “I know…” is open to public correction.) It seems possible that a people is persecuted for its religious beliefs precisely because of this feature of belief. Unlike something for which one needs to give an account—i.e., an “I know…” utterance—a belief requires no account. If there needs be no evidence for a belief, then there may be no evidence against a belief.