Occam’s Razor, also known as the law of parsimony (Latin: lex parsimoniae), requires that, when developing a hypothesis, entities are not to be multiplied beyond necessity. In other words, don’t make more assumptions about things not in evidence, to explain the evidence, than absolutely necessary. Ideally, don’t do it at all. However, if you’re at the bleeding edge of (y)our understanding of a phenomenon, then sometimes making some reference to an as yet unknown entity, given the facts of the matter, is necessary.
A favourite example of an unnecessary entity is phlogiston, which Lavoisier dismissed, thus:
If all of chemistry can be explained in a satisfactory manner without the help of phlogiston, that is enough to render it infinitely likely that the principle does not exist, that it is a hypothetical substance, a gratuitous supposition. It is, after all, a principle of logic not to multiply entities unnecessarily (Lavoisier 1862, pp. 623–4).
Note that I parenthetically implied, above, that it may be “your” understanding of a phenomenon, as distinct from “our” understanding of a phenomenon, that requires additional explanatory entities. Lavoisier’s understanding of chemistry, for example, was as good as it could have been at the time, and he seemed to feel no need for phlogiston to explain flammability. Which nicely leads to this pithy admonition from Kent Holsinger:
Since Occam’s Razor ought to be invoked only when several hypotheses explain the same set of facts equally well, in practice its domain will be very limited…[C]ases where competing hypotheses explain a phenomenon equally well are comparatively rare (Holsinger 1980, pp. 144–5).
However, we find ourselves in a time and place where alternative hypotheses must contend with “alternative facts”, which, if we’re not being coy, are lies. Yes, I could temper that claim with a digression on the individual’s state of knowledge, and intent, and all that, but I think it pretty clear that if the person making the statement calls it an “alternative fact”, they know it is a lie.
Opinions are a different matter, of course. Differences of opinion can be resolved when there is agreement on the facts of the matter. The issue then becomes the amount of weight each party applies to each of the given facts, and why. It is very much harder to come to an agreement when one can’t even agree on the facts of the matter, indeed, it is generally fruitless.
This latter fact might be the basis for a good case for theists and atheists never to debate, as there are a great many facts not agreed upon, foremost among which is the existence of God.
The use of God as an explanatory entity is a moveable feast. God can be used to explain individual things, and God can be used to explain the whole universe. At least that’s the claim… or rather, claims; these are quite distinct claims. God being the basis of/reason for human morality is entirely different to God creating the universe and everything in it. The claim about morality is a subset of the claim about the whole universe. Human morality is instantiated in many billions of people, past and present; the universe, whilst containing many billions of entities is, itself, a single entity.
Compared to the universe, God is just one more entity. However, one more than one is a 100% increase in the entities involved, and that is extravagant. However, compared to all of the individual things in the universe, depending upon how you tally them up, God is just another entity amongst many trillions.
I previously pointed to the fact that two people with different beliefs about fundamental facts are unlikely to be able to argue to a point of agreement. Certain facts need to be agreed upon, or a debate is pointless. Evolution, creationism/intelligent design, or some third hypothesis, is one such case.
If God is responsible for some kind of creative act that is not evolution by natural selection, then she/he/it is also responsible for creating the thousands of red herrings that have been found to support evolution by natural selection, from genetics to stratigraphy. (To test our faith, presumably.) Alternatively, if God is responsible for some kind of creative act that uses evolution by natural selection, then she/he/it conceals the mechanism by which that meddling occurs; because the mechanism that we have discovered, by which it seems to occur, has “no need of that hypothesis”.
Note that in both of the above scenarios, whilst God is just one more entity than what we see at work in the universe, and as such, not especially extravagant, each claimed interference also gives rise to an entity or occurrence within the universe, and a mechanism that continues to work (especially where the nudge to evolution is instantiated in the DNA). So every claimed missing link, every gap that God supposedly fills, is another entity. Rather than an elegant, single entity that, by its presence, explains everything, the God hypothesis is, in fact, legion, and thus an extravagance.
The above versions of the God hypothesis give rise to the ideas that, either God created man, as we now understand man to be, or; God caused humanity to evolve by manipulating the evolutionary process. In either case, humans ended up with brains that are the most complex entities known to us. In addition, irrespective of which of the two hypotheses the theist prefers, the idea that God knows us, and has a plan for us doesn’t just add to but multiplies the complexity being ascribed to God.
In order to successfully manipulate someone with a human brain, or the facts of that beings circumstance, one must have a more complex brain or be a collection of such brains working in concert. In order to be as involved in our lives as devout believers claim, and to be truly omniscient (not merely knowing more than a creationist), God must have a mind (as opposed to a brain, as that’s “merely” physical) many more times complex than all of the human brains that have existed, or will exist. So, as an intelligence, God must be many quadrillions of times more complex than the most complex entity in the universe. Not merely cleverer than the sum of the 7.2 billion brains on the planet, but many orders of magnitude cleverer.
The Big Giant Head
So, it’s not just the case that God would be a single entity if God were real. God would give rise to many billions of entities, that God is used in explaining – even if we only consider our own DNA and collective synapses – thereby becoming part of the tally of entities that God is. The intelligence ascribed to God, given humanity’s meagre intelligence from a highly complex brain, implies a level of complexity for God that is easy to claim with the wave of a hand, but very much more difficult to justify in the light of what we know about the complexities of our brains. Likewise, with gaps in the fossil record, just insert some God ‘No More Gaps’ and away those gaps go, but those gaps are now inhabited by entities that are included within the God concept. They are not subsumed into the entity that is God.
God is either a single entity alongside the universe, and thus doubles the number of entities required by the explanation, and thus should be excluded as an unnecessary extravagance. Or, God is a collective noun for all of the gaps that he is invoked to explain, and is thus many billions of entities, and therefore an unnecessary explanatory extravagance. God can not be both, with the ability to switch, as necessary. Either way, God falls victim to the razor.