The universe can be described as a system governed by regular patterns. If it is a mechanistic system, then it is best understood as a collection of interrelated systems. For example: objects fall rather than float; dogs give birth to puppies rather than kittens or calves; biological kinds reproduce according to consistent patterns. These regularities extend indefinitely and form the basis of our understanding of how the world works.
Religion, however, often proposes that the universe is not truly closed. It suggests that if God had a sufficient reason, events radically inconsistent with observed regularities—such as a male dog giving birth to a calf—could occur. Such an event would be called a miracle. On this view, a system that behaves regularly only when left alone is not genuinely closed. If divine purposes can override any regularity, then no system is ultimately insulated from intervention.
Religious thinkers sometimes argue that the “laws of nature” merely describe what usually happens, not what must happen. These laws are said to be descriptive rather than prescriptive: they record patterns but do not enforce them. As a result, exceptions are said to be possible without contradicting the laws themselves.
However, this distinction does not resolve the issue. A law can be both descriptive and prescriptive at the same time. The fact that we learn laws from observation does not imply that they lack governing force. A system of laws may consistently regulate behavior even if our knowledge of it is empirical.
Moreover, appealing to miracles in this way risks undermining the evidential basis of those laws altogether. If nature appears orderly only because countless miracles conceal deeper irregularities, then observation loses its reliability. In that case, evidence is no longer allowed to function as evidence. The problem is no longer whether the evidence is sufficient to justify belief in miracles, but whether evidence is permitted to count for anything at all.
What believers often do, intentionally or not, is define the universe as regular in a way that guarantees the possibility of exceptions. This reflects a prior commitment to miracles rather than a conclusion drawn from evidence. The desire for exceptions becomes more important than determining whether exceptions actually exist. In this sense, belief drives interpretation rather than the reverse.
For clarity, let us define terms. Matter refers to physical, material substances. Spirit refers to entities that are said to exist without material form, a concept commonly associated with religion.
Christians often object to the philosopher David Hume, who argued that miracle claims should not be accepted because they conflict with the uniform experience of nature. Hume is frequently interpreted as defending naturalism: the view that reality is a closed system governed by impersonal forces, where events unfold through chance, necessity, and mechanical processes. On this view, even the order of the universe arose without supernatural design.
Many religious critics object to naturalism because it reduces reality to impersonal mechanisms. However, introducing supernatural spirits does not necessarily solve this problem. There is no guarantee that non-material beings are intelligent, purposeful, or personal. They could be just as mechanical and impersonal as material particles. A spirit world could function according to fixed rules and blind processes just as easily as a material one.
If the concern is that a purely mechanical universe leaves no room for meaning, purpose, or love, then positing spirits merely relocates the issue. A supernatural worldview can be just as naturalistic in outlook as a material one. A reality made of spirit can be as indifferent and rule-bound as one made of matter.
Religion and spirit do not have a monopoly on the idea that reality is “more than just things.” Yet spirit is often presented as inherently special and as a genuine alternative to mechanism, largely through religious tradition rather than argument.
Finally, there is no reason to assume that if nature allows exceptions, the supernatural does as well. The supernatural could be equally rigid or even more restrictive. It might decree that the dead never rise, or that extraordinary events occur only under obscure conditions. We have no independent knowledge of its rules.
In conclusion: belief in spirits is compatible with a thoroughly materialistic or mechanistic way of thinking. Rather than resolving the doubts raised by Hume about miracles, the introduction of the supernatural deepens them.