One important aspect of philosophical arguments is whether or not there exist any “default positions.” That is, if I am trying to convince someone about X and that person is trying to convince me of the opposite of X, is either of us in some kind of default position? When is an idea innocent until proven guilty? Guilty until proven innocent? Or when does an idea start off somewhere in the middle – where all relevant viewpoints equally are required to prove their point?
The technical term used to lay out these distinctions is the burden of proof. The burden of proof is exactly what it sounds like – it is a burden or obligation to prove what you are saying. So, the questions of the previous paragraph are summarized in one question – in any disagreement, who has the burden of proof?
The most commonly discussed and well-known application of the idea of the burden of proof comes in criminal trials. In a criminal trial, the jury is instructed that the accused is to be considered innocent until proven guilty, and that the evidence must point to guilt beyond a reasonable doubt. This is a clear affirmation that between the two sides of a trial – the defense and the prosecution – only the prosecution carries a burden of proof. There is, in this case, a default assumption that the man or woman on trial is innocent. The defense is not required to prove innocence, only to show that the prosecution cannot prove guilt.
But is this always so? Are we to always use the innocent until proven guilty standard? And if so, how do we even know which side is the “innocent” side? Well, really the answer is that no, we do not always use that standard. There are other situations where it is appropriate to apply a similar standard, but most situations are not like that. In most situations, the fact of the matter is that both sides of a debate have a burden of proof. Why is this so? To explain, it would help to provide a rule of thumb for when a person involved in a debate carries a burden of proof. After making the rule of thumb clear, we can go back and add some additional details about some special situations where the rule of thumb is not considered applicable.
Generally speaking, the burden of proof falls on any person who makes an objective truth claim. A truth claim is just any claim that “such-and-such is the case,” “such-and-such is true,” “such-and-such is false,” or “such-and-such really happened.” Not everything is a truth claim. For example, if you mother tells you to clean your room, that isn’t a truth claim – rather, it is a command. Questions also are not truth claims – they are just questions. Perhaps a person asking the question is trying to get you to think of some truth claim – maybe they are asking a leading question – but in and of itself a question makes no claims. (To be grammatically precise, truth claims use the indicative mood, but don’t get bogged down in fancy language, we all have a pretty strong intuitive understanding of what truth claims are and are not when we slow down and think about it).
What then do we mean by an objective truth claim? In this context, by objective I mean external to our own consciousness. For instance, the sentence “I am happy today” is a truth claim, but it is not objective in the sense I am using it, because emotional states like ‘happiness’ reside in your consciousness. The reason that this kind of distinction is important is because it isn’t really possible for anybody to bring any evidence against your claim that you are happy – they do not have access to your thoughts and feelings, so how would they know? For this reason, a person who says “I am happy right now” has no burden of proof at all – their statement is to be accepted at face value as a statement of their perceptions of their own emotions. Of course, sometimes people are in denial about things, so people can be mistaken about certain things – but to show that this is the case would require a great deal of convincing from the outside.
Putting aside for now the abstract discussion – let’s look at examples that matter. Let’s take for instance politics. If a Democrat and Republican are debating some topic, who has the burden of proof? For very nearly every political issue I can think of, both sides have equal burdens of proof, since each side is making a claim about the way the world around us is. To decide whether it would be better to raise or lower taxes, for example, both sides must bring forward their best evidence of their own conviction, and then the evidence can be evaluated and conclusions can be drawn.
Another common example is in matters of religious debate. For the most part, in the context of a public discourse, every religious perspective has its own burden of proof. Christians, Muslims, Hindus, Jews, and atheists are all making claims that a certain deity exists or doesn’t exist, that certain things do or don’t happen in the afterlife, that certain events in history happened or didn’t happen. The exception to that rule is agnostics – because the position of an agnostic is that they don’t know what to believe, they aren’t making an truth claim about the outside world. So agnostics carry no burden of proof – everyone else does. So far as I can tell, every group seems to realize this except for some subset of the atheists. Many of the atheists that say things like they “only lack a belief in God” and that “you can’t prove negatives” are, whether they realize it or not, putting up a smokescreen to make themselves look like agnostics when they aren’t. Surely, many of these people really do believe these things and many who say this actually are agnostics. But many of those who say they merely “lack belief” will also actively try to convince you that there is no God – which is a truth claim and carries with it a burden of proof. The claim that there is no God and the burden of proof that comes with it has been part of the very definition atheism for the entire history of philosophy (and still is – some very recent popular-level thinkers have tried to redefine the word atheist to mean something more like agnostic, but academic philosophy doesn’t take that seriously as far as I know).
In summary, very nearly all actual debates that people engage in and nearly all questions that people really care about will be like the examples above – these are situations in which all sides carry a burden of proof. But there are some areas where this is not so. The epistemological term basic belief, or properly basic belief, is often used in these situations. In short, a properly basic belief is a belief that is so foundational and so deeply integrated into our ability to think at all that no burden of proof is required. Going back to the criminal trial example, a properly basic belief is like the “innocent” verdict – we are allowed to assume that our properly basic beliefs are correct unless it is shown to us beyond a reasonable doubt that they are mistaken. Broadly speaking, properly basic beliefs include things like our sensory perceptions and beliefs about our own thoughts and feelings. It may help to see some more specific examples.
One helpful example of what properly basic beliefs look like is my belief that I have a body. While technically someone could try to convince you that you’re only hallucinating your body or that you are in “the matrix” and that you don’t actually have a body (at least not like the one you think you have), the immediate experience of seeing and controlling your body every day is enough to safely conclude that you actually do have a body. We don’t have to prove to people that we have a body – we just know that we do. A similar example is the belief the people you talk to every day are not “robots” but have thoughts and feelings in the same kind of way that you do – in other words, that there are other minds that besides my own. Is it possible that I am really the only thing in the universe and am constantly hallucinating everything around me? Well, you can’t really disprove that. But that doesn’t mean we have to take such an accusation seriously either. We are being perfectly reasonable when we assume that people we talk to also have minds, because this is a properly basic belief and carries no burden of proof.
Hopefully, this discussion of the burden of proof, truth claims, and properly basic beliefs helps to shed light on the reality that, more times than not, being intellectually responsible requires bringing forth some form of evidence for that which we believe. And for my Christian readers, the New Testament explicitly tells us that our faith in Jesus is one of the things that we should be prepared to defend using evidence, for we are told:
“Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have.“ – 1 Peter 3:15 (NIV)
Having put down at least an initial discussion about having intellectual integrity in the importance of using evidence to defend what we believe, we can move on to a discussion about how we can think about evidence itself.