If Occam's razor supports naturalism over theism, then why was William of Ockham, its author, a theist and not a naturalist? [closed]

Question

From Wikipedia:

In philosophy, Occam's razor (also spelled Ockham's razor or Ocham's razor; Latin: novacula Occami) is the problem-solving principle that recommends searching for explanations constructed with the smallest possible set of elements. It is also known as the principle of parsimony or the law of parsimony (Latin: lex parsimoniae). Attributed to William of Ockham, a 14th-century English philosopher and theologian, it is frequently cited as Entia non sunt multiplicanda praeter necessitatem, which translates as "Entities must not be multiplied beyond necessity", although Occam never used these exact words. Popularly, the principle is sometimes paraphrased as "The simplest explanation is usually the best one."

This philosophical razor advocates that when presented with competing hypotheses about the same prediction and both hypotheses have equal explanatory power, one should prefer the hypothesis that requires the fewest assumptions, and that this is not meant to be a way of choosing between hypotheses that make different predictions. Similarly, in science, Occam's razor is used as an abductive heuristic in the development of theoretical models rather than as a rigorous arbiter between candidate models.

Did William of Ockham ever attempt to apply his razor to his own theistic worldview? Why was William of Ockham a theist and not a naturalist despite having developed a tool that in principle could support naturalism over theism (or even solipsism over naturalism, as discussed in Does Occam's Razor favor metaphysical solipsism?)?

Answer 1

1. Ockham’s razor is a methodological tool.

   It discriminates between good argumentation and bad argumentation. But it does not decide between theism and naturalism.

2. One cannot discriminate between theism and naturalism solely on the basis of Ockham’s razor.

   First of all one has to weight the arguments on both sides. This includes to assess the clarity of the concepts, the consistency of the argumentation as a whole and the explanatory power of both approaches.

3. William of Ockham was a Franciscan friar, educated as a Catholic theologian. He did not agree with Thomas Aquinas concerning every statement of their theological doctrine. But I do not see any reason why Ockham should have changed theism against naturalism.

Answer 2

A person’s belief based on a tool says nothing about the significance of the tool. Almost everyone in the world believes that evidence, for example, is crucial to one’s beliefs. Flat earth and global earth believers both believe they have evidence for their respective positions. The fact that these differences exist does not imply that evidence is a useless tool.

Anyone can gerrymander any tool to support their worldview: that is the (unfortunate) nature of philosophy. Arguably though, because theism contains everything that naturalism contains in its world plus more, there doesn’t seem to be any reason at all for preferring theism over naturalism with respect to simplicity only.

Of course, one can argue that theism may have greater explanatory power than naturalism even if it is less simpler, but that is not what was asked about.

Answer 3

That's like asking: if a hammer is best used by swinging it in an arc, why did the inventor of the hammer use it with a stomping motion instead. (Disclaimer: I just made that up)

We evaluate some tool and determine how to appropriately use it by its own merits. This is independent of how the inventor of that tool used it.

We might consider Occam's razor by looking at the natural world and seeing what sorts of claims turns out to be true and when it's reasonable to believe something. We might conclude that claims are unjustified if they have no explanatory or predictive power, if they explain evidence that we can explain by other claims we already accept without any clear explanatory advantage, if they create more "just so" facts, or if they're interchangeable with other comparable claims (related answer). In this way, we might reject theist claims.

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As for why William of Ockham was a theist (i.e. believed a false/unjustified thing, according to the given premise), that's really not that different from why anyone else believes unjustified things. That can happen because of various cognitive biases (if not due to a lack of information or being given false information).

William received religious education starting from elementary school. He studied theology. This is not exactly an environment free from social pressure and dedication to a particular belief, which can heavily influence beliefs. Never mind that we've learnt so much since the Middle Ages. And that was not exactly a time known for treating non-believers well. Case in point: at one point, his commentary was condemned as unorthodox and he was ordered to defend himself before the papal court. Later, he argued that the pope was a heretic and spent the last years of his life living in exile. This wasn't even for challenging the fundamental truth on which their religion was based (he disagreed with the church's infallibility, which seems fairly relevant).

In modern times, there's much more diversity in beliefs and arguments, and it's a lot more acceptable to challenge and disagree with religious belief (certainly not everywhere, and not even everywhere in the US, but at least in a lot of places). If he were born in modern times, I think it's at least plausible to think he might have ended up as an atheist (but obviously this is highly speculative, especially given that I'm not really familiar with his writings).

Answer 4

Occam's razor prefers theism, because it allows for a much simpler description of reality. To demonstrate this, let's use Kolmogorov complexity, with the addition that the Turing machine can have access to a halting oracle, a stand-in for a divine being. A divine being worthy of the name should at least possess the equivalent of a halting oracle.

Kolmogorov complexity without a halting oracle is represented by KC(X).

Kolmogorov complexity with a halting oracle is represented by KCO(X).

Kolmogorov complexity is defined as the length of shortest computer program defined with the reference Turing machine that generates X.

The key point is that having access to a halting oracle makes KCO a superset of KC, within a small constant. If a program is sufficient to generate X without calling out to a halting oracle, then KCO(X) will be the same as KC(X), within the small constant. However, if the program can be made shorter by calling out to a halting oracle, then KCO(X) will be shorter than KC(X). So, within the small constant, KCO(X) <= KC(X) for all X. Consequently, per Occam's razor, KCO is always the preferred mechanism for explaining X.

Per the Church-Turing thesis, a Turing machine can compute anything that can be performed by natural processes. Consequently, a Turing machine is an upper bound on the explanatory capability of naturalism. KC(X) is thus the best possible naturalistic explanation of X.

Since we've seen that KCO(X) <= KC(X), and thus KCO is always preferred to explain any X over KC, then this means that KCO is a better explanation than naturalism for all Xs.

Finally, since KCO is a lower bound on the explanatory capabilities of a divine being worthy of the name, then this means that theism is always a better explanation for every X than naturalism, according to Occam's razor.

In response, someone may say, like Dawkins, that the divine being is necessarily more complex than X. Consequently, KCO is just hiding the complexity in the oracle. However, the medievals believed in divine simplicity, which is the divine being is completely simple. It has a complexity of 0. Therefore, KCO is not hiding any complexity.