In his book Faith and Belief (1979), the Canadian scholar Wilfred Cantwell Smith analyzes these two terms from a variety of angles, including the history of their usage. Smith notes that many people use the words faith and belief in a more or less interchangeable manner, as if they were synonyms; yet, the two words have very different meanings in contemporary English.
Smith shows that the confusion surrounding these words has resulted from the fact that before the seventeenth century these words did carry rather similar or at least overlapping meanings, but that over the last three hundred years or so their meanings have undergone a gradual but very important divergence. Even though the modern meanings of faith and belief are quite different, some of us are either not fully cognizant of this difference or for some reason prefer to use them in their premodern sense, especially when speaking in a religious context. The resulting ambiguity has contributed to a major misunderstanding of the nature of religion.
Let’s begin with the word belief. In modern usage, Smith says, believing “is the holding of certain ideas” and, as such, represents “an activity of the mind.” At this basic level of denotation, the question of certainty or truth does not arise.
What does it mean to hold an idea in the mind? Upon introspection, we can easily notice that our mental life is always in a state of flux. Thoughts appear in the mind, give rise to other thoughts, and then disappear. The process, however, is not random. Whether or not we are consciously aware of them, certain thoughts tend to occur repeatedly over an extended period of time, until they establish themselves as tracks or pathways in the mind. These, in turn, form mental patterns along which most of our everyday thinking tends to flow. This suggests that while our mental world does not remain static from one moment to the next, in the long-run it does develop certain patterns that may be described as stable, if not permanent. With sufficient introspective skill, we can learn to notice these patterns, though it takes extraordinary effort to recognize the subconscious thoughts that are responsible for creating these patterns in the first place.
Insofar as our habitual patterns of thought allow themselves to be articulated as ideas, we may call them beliefs. In other words, a belief is an idea that we hold in our mind over an extended period of time. It is essentially a thought in the head, though a relatively stable one.
In addition to the denotative meaning of belief as an idea held in the mind, Smith demonstrates that the contemporary usage of this word suggests two significant connotations. When these connotations are taken into account, it becomes clear that the modern meaning of the word belief represents a concept that is in opposition to what most people think of knowledge. According to Smith, the commonsense meaning of the word knowledge involves both certitude and correctness, neither of which is part of the commonsense meaning of belief.
Consider the impression we convey when we start a sentence with “I believe,” as opposed to “I know.” In the former case, the speaker implies a lack of full confidence in what he/she is about to assert, while allowing that the audience has every right to disagree. In the latter case, the speaker is not only completely sure but also assumes that the truth of what he/she is about to assert should be obvious to other people. According to Smith, the phrase “I believe” is intended to give the impression of an “open neutrality as to the correctness or otherwise of what is believed.”
To reiterate, when I begin a sentence with “I believe,” I am implying one or both of the following qualifications: (1) this is my current opinion or position, but I may be wrong and I may change my mind in the future; (2) I am okay with the fact that there are many people who do not share my views, since the issue is open to multiple interpretations.
We should also keep in mind that the phrase “I know” is often left unsaid; for the very absence of “I believe” frequently implies “I know,” even when the latter phrase is not actually uttered. For example, notice the difference between “I believe it is raining” and “It is raining.” In the latter sentence, “I know” is tacitly implied.
To appreciate the significance of the difference between “I believe” and “I know,” consider the famous exchange between the Swiss psychologist Carl Jung and a BBC reporter that took place during an interview in 1959. John Freeman, the interviewer, asked: “Dr. Jung, do you believe in God?” Jung said: “Believe? I don’t need to believe — I know.”
This exchange nicely illustrates what Smith means when he emphasizes the modern distinction between believing and knowing. When faced with the question “Do you believe in God?” most people are likely to respond with “yes,” “no,” or “may be.” A philosopher or theologian may demand that the word “God” is defined before they can give an answer. Carl Jung, however, recognized that the most problematic word in the question was not “God” but rather “believe.” In effect, Jung gave an answer that offered much more than what the interviewer had asked (or hoped) for. Jung said, essentially, that we “believe” only when we do not “know,” and that if we “know” then there is no need for us to “believe.” What is called believing is merely an inferior substitute for those who don’t (or not yet) have the real thing, i.e., knowing.