The aphorism "absence of evidence is not evidence of absence" is often invoked in discussions about theism and atheism. However, this statement is not universally true. In certain contexts, absence of evidence can indeed be evidence of absence, particularly when evidence would be expected if a claim were true. This principle is often analyzed through the lens of Bayesian reasoning and has significant implications in the debate over the existence of God, especially in relation to the argument from divine hiddenness. In this article, we will explore when absence of evidence constitutes evidence of absence and what this means for theism.
Bayesian Reasoning and Absence of Evidence
Bayesian reasoning provides a framework for updating our beliefs in light of new evidence. According to Bayes' theorem, we adjust the probability of a hypothesis being true based on the likelihood of observing the evidence given that hypothesis. If we would expect certain evidence to be present if a hypothesis were true, and yet we do not observe this evidence, the probability of the hypothesis being true decreases.
For instance, if we hypothesize that there is a cat in a room, we would expect to find evidence such as cat hair, a litter box, or the sound of meowing. If we thoroughly search the room and find none of these indicators, the absence of evidence becomes evidence of absence, reducing the likelihood that there is a cat in the room.
Divine Hiddenness and Theism
One of the most prominent discussions where absence of evidence is debated in relation to theism is the argument from divine hiddenness, especially as developed by philosopher J.L. Schellenberg. Schellenberg's argument is not that a loving God must provide coercive or undeniable proof. Rather, he argues that if a perfectly loving personal God exists, then God would always be open to a meaningful relationship with any finite person capable of such a relationship. Since conscious relationship with God requires belief that God exists, there should be no nonresistant or nonculpable nonbelief: no sincere person who is open to God, yet unable to believe. The apparent existence of such people is then taken as evidence against the existence of a perfectly loving personal God.
Schellenberg's argument hinges on expectations generated by the kind of God under discussion. If God is omniscient, omnipotent, and perfectly loving in a personal sense, then it is reasonable to ask why any capable and nonresistant person would remain unable to enter into conscious relationship with God. On this formulation, hiddenness is not merely the complaint that God has failed to meet a human demand for spectacle; it is an argument from the apparent mismatch between perfect divine love and the existence of sincere, reflective, morally serious nonbelievers. If such cases really exist, they provide at least prima facie evidence against that specific conception of God.
Expectations and Conceptions of God
A critical aspect of this debate is the conception of God that underlies the expectations for evidence. The argument from divine hiddenness is strongest against a personal, perfectly loving God who desires relationship with human beings. It is weaker against a more impersonal first cause, a deistic creator, or a deity whose central aims are not relational in this sense. Critics may therefore respond by challenging the relational premise, by arguing that divine love need not require immediately available belief, or by proposing that there are goods connected with ambiguity, seeking, moral formation, or freedom. However, these replies must do more than state that God's reasons are unknown; they need to explain why the existence of apparently nonresistant nonbelievers is not surprising on theism.
Furthermore, expectations of evidence can vary significantly depending on background assumptions. Some theists argue that the case for God is cumulative rather than dependent on one decisive sign, drawing on considerations such as the existence of the universe, order in nature, consciousness, moral experience, religious experience, and the intelligibility of reality. Atheists may reasonably dispute the strength of these considerations, but the point is that the relevant question is not simply whether there is laboratory-style evidence. It is whether, given the hypothesis of a perfectly loving personal God, we should expect more accessible and less ambiguous evidence than we in fact find. Appeals to 'faith' or 'spiritual insight' are not enough by themselves unless they are connected to reasons that a sincere outsider can assess without already assuming theism.
Addressing Counterarguments
One common response to Schellenberg's position is divine inscrutability, sometimes associated with skeptical theism. This response holds that God's reasons for permitting hiddenness might be beyond human comprehension. Properly stated, this can weaken the inference from 'I see no good reason for hiddenness' to 'there is no good reason for hiddenness.' But as a bare possibility, it is not decisive. In Bayesian terms, inscrutability lowers our confidence about what we should expect if God exists, but it does not automatically erase the evidential force of hiddenness. If used too broadly, it can also undercut positive theistic arguments that rely on claims about what God would probably do.
Another response is that evidence of God may be person-relative: some people may find religious experience, moral awareness, contingency, or the order of nature evidentially powerful, while others do not. It is also true that cognitive biases and cultural influences affect how people interpret evidence. But this point cuts both ways: believers and nonbelievers alike are shaped by psychology, upbringing, and community. A serious reply to hiddenness should not imply that unbelief is always due to closed-mindedness. It must account for the apparent existence of intellectually honest, morally serious people who seek truth and yet remain unconvinced.
These counterarguments highlight the complexity of evaluating absence of evidence in matters of theism. They underscore the importance of clearly defining the expectations for evidence based on the particular conception of God being considered.
Conclusion
In conclusion, absence of evidence can indeed be evidence of absence when the missing evidence is something we should reasonably expect to find if the claim were true. In the context of theism, this principle is forcefully expressed in the argument from divine hiddenness. The argument does not refute every possible form of theism, but it is a serious challenge to belief in a perfectly loving personal God, especially if there are genuine cases of nonresistant nonbelief. Responses based on divine inscrutability, person-relative evidence, or human cognitive limitations may reduce the argument's force, but they should not be treated as quick dismissals. They need to show why hiddenness is not surprising on the particular theistic view being defended.
This analysis does not resolve the debate in favor of atheism or theism but highlights the nuanced considerations involved in evaluating claims about the divine. It underscores the necessity of scrutinizing our expectations of evidence and the assumptions that underpin them.