A few days ago I argued that god was completely irrelevant, and thus that we could simply discard the idea of god completely, without even worrying about god’s existence. But not everyone understood the nature of that claim, some thought that I was arguing directly for god’s non-existence or that somehow the idea of god contained a logical flaw. I think that this misinterpretation springs from failing to properly understand the concept of irrelevance. And since irrelevance is a useful intellectual tool, both in science and in philosophy, perhaps I should elaborate on it.
A claim that something (X) is irrelevant, completely spelled out, involves three parts: that thing (X) defined categorically*, a set of phenomena, and a theory not involving X. Before we get to the definition itself let me start by mentioning that we must be considering something defined categorically because it is impossible for an ostensive definition to be irrelevant, given that the ostensive definition is in terms of causation or explanation (the thing that causes …, the thing that seems …, or the thing that explains …). As I outlined in a previous post most of the things we encounter, and the basic entities in scientific discourse, are best thought of as being defined ostensively. Which seems paradoxical, since if we start with ostensive definitions how do we ever arrive at something categorical which we then call irrelevant? I claim that categorical definitions arise from ostensive definitions through formal or informal theorizing. We begin with an ostensive definition for something like a chair in the form “that thing that is chair-like in the corner”. This definition leaves the exact nature of “that thing” undefined. And so we theorize about it, and construct an idea of “the chair” that is an object with certain properties. Of course this is not to say that we could simply save every idea by leaving it defined ostensively. Perhaps we could save it from irrelevance, but then for any reasonably complex idea we can probably argue that it simply doesn’t exist. For example, in the case of the chair we can argue that there is no one thing that is chair-like in the corner, only a collection of things (particles) that are together chair-like. In the case of god we can argue that there is no one thing that is the cause of the universe, the source of ethical norms, and that cares about our existence. Ect, ect, ect.
Going back to what is required to formulate the definition, I also mentioned we also need to describe a set of phenomena, or things that need to be explained, which we are claiming our X is irrelevant to. Generally the phenomena in question are self-evident, for example in the context of science the phenomena are simply physical events in general. The reason that we need to specify which phenomena we have in mind is because there are things that are irrelevant to some phenomena while being supremely relevant to others. For example, ethics is irrelevant to the behavior of electrons, but it is relevant to how people should act. And a chair is irrelevant to physical events (only the particles that make up what we think of as the chair are), but there are macroscopic descriptions of events in which the chair does play a role. (For example, as the thing that is supporting me.) Of course this raises the further question as to whether everything can be reduced to a description in terms of physical phenomena alone, in which case if something is relevant at all it must be in some sense a convoluted description of physical facts or kinds of physical situations. Personally I do think such reductions are possible, but whether they are or not isn’t important here, only to note that the possibility of such reductions doesn’t threaten the idea that we can talk about categories of phenomena that aren’t obviously physical.
And finally we have a theory that doesn’t mention X. By theory in this context I simply mean an uncontroversial understanding of the way things work. Given these three things irrelevance is easy to define. X is irrelevant to the phenomena if explanations can be given for those phenomena in terms of our uncontroversial theory that doesn’t include X which are at least as good as the explanations involving X. I’ll leave what makes an explanation good intentionally ill-defined here, since that is a thorny issue of its own, but we can understand it loosely as meaning that one explanation is better than another if it provides more information about the event than we previously had and that we can use that same information to predict or explain other events. This is what makes physics a better explanation than magic. Even though physics actually explains less than magic (because we can claim magic as the rationale behind every event) physics is a better explanation because physics gives us an answer to “why?” that leaves us knowing more, and better able to make predictions; magic is “transcendental”, once we appeal to magic we can’t expect any further answers as to why magic made things turn out one way instead of another. And we can define what it means for some X to be completely irrelevant, in these terms, as something which is irrelevant to every phenomena that needs explaining.
Now that we have a definition of irrelevance in hand let’s apply it to an episode of the history of science, which will hopefully clear up any ambiguities in the above definitions. Specifically let us look at the idea of a “vital force”. Before chemistry was understood as well as it is today it seemed that living things could not be sufficiently explained by the existing chemical and physical theories. They seemed too complicated, and no chemical reactions were known which could explain their workings. Thus the vital force was introduced, ostensively, as that which allowed living things to behave in ways unavailable to non-living things, specifically to breathe, eat, grow, heal, and reproduce. But the vital force didn’t remain ostensively defined for long, by its name alone people came to think of it as a kind of substance or energy that resided inside animal and plant bodies, and which provided these extra abilities. Chemistry, however, progressed, and soon it became apparent that chemical explanations could be given of breathing, eating, growing, ect. Our: X – the vital force. The phenomena – breathing, eating, … The theory – chemistry. And since chemistry could explain all the phenomena better than the vital force could the vital force was discarded as irrelevant. No one ever carried out any physical theorizing in order to disprove the possibility of a vital force (such as by showing that it violated the conservation of energy); no one needed to. Once it was shown to be irrelevant there was no longer any rational reason to postulate its existence, and so it was simply dropped from the discussion.
The same can be said about magic, that physics explains all the physical phenomena, or at least provides better explanations than magic, and so magic is irrelevant, and hence to be rationally discarded from consideration without any formal disproof. And, as I claimed last time, the same can be said about god. Although in the case of god the fact that god isn’t required to explain the physical phenomena is only part of the story, we also need to show that god isn’t required to explain any number of the more philosophical issues that he is sometimes invoked for, such as the existence of ethics, how life can be meaningful, ect. And I have shown that god is irrelevant to these issues as well by showing that at least equally good explanations/solutions can be given without appeal to god. And thus god is irrelevant, and thus the idea of god should simply be discarded, like the idea of the vital force was, without even bothering to directly address whether god could exist.
Note: at this point to argue that god shouldn’t simply be rationally discarded requires that you produce some phenomena for which god is a better explanation (or preferably, the only explanation) than physics + philosophy. No other reasons, for example that belief in god makes you feel better, provide a rational reason to hold onto god, any more than they would provide rational reason to hang onto the vital force if its existence made you feel better.
* A categorical definition is simply one that defines something by appeal to a list of properties it has (the thing that is …).