Is the fact that our universe contains fine-tuned life evidence that we live in a multiverse? Ian Hacking and Roger White influentially argue that it is not. We approach this question through a systematic framework for self-locating epistemology. As it turns out, leading approaches to self-locating evidence agree that the fact that our own universe contains fine-tuned life indeed confirms the existence of a multiverse. This convergence is no accident: we present two theorems showing that, in this setting, any updating (...) rule that satisfies a few reasonable conditions will have the same feature. The conclusion that fine-tuned life provides evidence for a multiverse is hard to escape. (shrink)

Given the laws of our universe, the initial conditions and cosmological constants had to be "fine-tuned" to result in life. Is this evidence for design? We argue that we should be uncertain whether an ideal agent would take it to be so—but that given such uncertainty, we should react to fine-tuning by boosting our confidence in design. The degree to which we should do so depends on our credences in controversial metaphysical issues.

Does the claimed fine-tuning of the constants of nature for life give reason to think that there are many other universes in which the constants have different values? Or does the inference from fine-tuning to a multiverse commit what Hacking calls the inverse gambler’s fallacy? The present paper considers two fine-tuning problems that seem promising to consider because they are in many respects analogous to the problem of the fine-tuned constants. Reasoning that parallels the inference from fine-tuning to a multiverse (...) seems prima facie adequate in these problems. However, it turns out that in both cases there are independent empirical reasons to believe the hypotheses that are analogous to the multiverse hypothesis. In the absence of such evidence, it would be coherent to raise the inverse gambler’s fallacy charge against the inference from fine-tuning to these multiverse-type hypotheses. In response to this finding, I suggest taking the possibility seriously that established standards of rationality may not allow us to decide whether the inference from fine-tuning to a multiverse is fallacious or not. The paper concludes by sceptically assessing the prospects for obtaining independent empirical evidence for concrete multiverse theories. (shrink)

According to the Fine-Tuning Argument, the existence of life in our universe confirms the Multiverse Hypothesis. A standard objection to FTA is that it violates the Requirement of Total Evidence. I argue that RTE should be rejected in favor of the Predesignation Requirement, according to which, in assessing the outcome of a probabilistic process, we should only use evidence characterizable in a manner available before observing the outcome. This produces the right verdicts in some simple cases in which RTE leads (...) us astray, and, when applied to FTA, it shows that our evidence does confirm HM. (shrink)

In this paper, I propose that, in addition to the multiverse hypothesis, which is commonly taken to be an alternative explanation for fine-tuning, other than the design hypothesis, the simulation hypothesis is another explanation for fine-tuning. I then argue that the simulation hypothesis undercuts the alleged evidential connection between ‘designer’ and ‘supernatural designer of immense power and knowledge’ in much the same way that the multiverse hypothesis undercuts the alleged evidential connection between ‘fine-tuning’ and ‘fine-tuner’ (or ‘designer’). If this is (...) correct, then the fine-tuning argument is a weak argument for the existence of God. (shrink)

We initially characterize what we’ll call existence problems as problems where there is evidence that a putative entity exists and this evidence is not easily dismissed; however, the evidence is not adequate to justify the claim that the entity exists, and in particular the entity hasn’t been detected. The putative entity is elusive. We then offer a strategy for determining whether an existence problem is philosophical or scientific. According to this strategy (1) existence problems are characterized in terms of causal (...) roles, and (2) these problems are categorized as scientific or philosophical on the basis of the epistemic context of putative realizers. We argue that the first step of the strategy is necessary to avoid begging the question with regard to categorization of existence problems, and the second step categorizes existence problems on the basis of a distinction between two ways in which an entity can be elusive. This distinction between kinds of elusiveness takes as background a standard account of inference to the best explanation. Applying this strategy, we argue that the existence of a multiverse is a scientific problem. (shrink)

Sometimes we learn what the world is like, and sometimes we learn where in the world we are. Are there any interesting differences between the two kinds of cases? The main aim of this article is to argue that learning where we are in the world brings into view the same kind of observation selection effects that operate when sampling from a population. I will first explain what observation selection effects are ( Section 1 ) and how they are relevant (...) to learning where we are in the world ( Section 2 ). I will show how measurements in the Many Worlds Interpretation of quantum mechanics can be understood as learning where you are in the world via some observation selection effect ( Section 3 ). I will apply a similar argument to the Sleeping Beauty Problem ( Section 4 ) and explain what I take the significance of the analogy to be ( Section 5 ). Finally, I will defend the Restricted Principle of Indifference on which some of my arguments depend ( Section 6 ). (shrink)

It is commonly argued that the fact that our universe is fine-tuned for life favors both a design hypothesis as well as a non-teleological multiverse hypothesis. The claim that the fine-tuning of this universe supports a non-teleological multiverse hypothesis has been forcefully challenged however by Ian Hacking and Roger White. In this paper we take this challenge even further by arguing that if it succeeds, then not only does the fine-tuning of this universe fail to support a multiverse hypothesis, but (...) it tends to favor a single-universe hypothesis instead. (shrink)

This paper has two aims. First, it points out a crucial difference between the standard argument from fine-tuning for the multiverse and paradigmatic instances of anthropic reasoning. The former treats the life-friendliness of our universe as the evidence whose impact is assessed, whereas the latter treat the life-friendliness of our universe as background information. Second, the paper develops a new fine-tuning argument for the multiverse which, unlike the old one, parallels the structure of paradigmatic instances of anthropic reasoning. The main (...) advantage of the new argument is that it is not susceptible to the inverse gambler’s fallacy charge. (shrink)

Many philosophers and scientists believe that we need an explanation as to why the laws of physics and the initial conditions of the universe are fine-tuned for life. The standard two options are: theism and the multiverse hypothesis. Both of these theories are extravagant and arguably have false predictions. Drawing on contemporary philosophy of mind, I outline a form of panpsychism that I believe offers a more parsimonious and less problematic explanation of cosmological fine-tuning.

I present and defend an “indexical” version of the Fine-Tuning Argument. I begin by outlining the dialectic between the Fine-Tuning Argument, the Multiverse Objection, and the This-Universe Reply. Next, I sketch an indexical fine-tuning argument and defend it from two new objections. Then, I show that such an argument is immune to the Multiverse Objection. I explain how a further augmentation to the argument allows it to avoid an objection I call the “Indifference Objection.” I conclude that my indexical version (...) of the Fine-Tuning Argument is no less cogent than the standard version, and yet it is immune to the Multiverse Objection. (shrink)

Jonathan Weisberg (2010 ) argues that, given that life exists, the fact that the universe is fine-tuned for life does not confirm the design hypothesis. And if the fact that life exists confirms the design hypothesis, fine-tuning is irrelevant. So either way, fine-tuning has nothing to do with it. I will defend a design argument that survives Weisberg’s critique — the fact that life exists supports the design hypothesis, but it only does so given fine-tuning.

Experiences tend to be followed by states for which they provide normative reasons. Such harmonious correlations cry out for explanation. Theories that answer or diminish these cries thereby achieve an advantage over theories that do neither. I argue that the main lines of response to these cries that are available to biological theorists—theorists who hold (roughly) that conscious subjects are generally biological entities—are problematic. And I argue that panpsychism—which holds (roughly) that conscious subjects are ubiquitous in nature—provides an attractive response (...) to these explanatory cries. Taken together, these considerations underwrite a kind of ‘psychophysical fine-tuning’ argument in support of panpsychism, one that is reminiscent of cosmological fine-tuning arguments in favor of multiverse hypotheses. (shrink)

This article explores theoretical conditions necessary for “quantum immortality” as well as its possible practical implications. It is demonstrated that QI is a particular case of “multiverse immortality”, which is based on two main assumptions: the very large size of the universe ; and a copy-friendly theory of personal identity. It is shown that a popular objection about lowering of the world-share of an observer in the case of QI does not succeed, as the world-share decline could be compensated by (...) merging timelines for the simpler minds, and because some types of personal preferences are not dependent on such changes. Despite large uncertainty about the truth of MI, it has appreciable practical consequences for some important outcomes like suicide and aging. The article demonstrates that MI could be used to significantly increase the expected subjective probability of success of risky life extension technologies, such as cryonics, but that it makes euthanasia impractical because of the risk of eternal suffering. Euthanasia should be replaced with cryothanasia, i.e. cryopreservation after voluntary death. Another possible application of MI is as a last chance to survive a global catastrophe. MI could be considered a Plan D for reaching immortality, where Plan A consists of survival until the development of beneficial Artificial Intelligence capable of fighting aging, Plan B employs cryonics, and Plan C is digital immortality. (shrink)

Since modern physicists made more and more advances in precisely measuring the fundamental constants in nature, cosmologists have been confronted with this problem: how do we declare that nature’s constants are fine-tuned for the emergence of life? Many cosmologists assume nowadays that the big bang universe originates from a multiverse that consists of very many universes. Some of these must be fine-tuned for life. A fascinating question arises: Would there be any chance on a life after our death in this (...) multiverse? In this paper, I show two things about the multiverse. First, universes in the multiverse acquire an unlimited amount of additional fine-tuning for intelligent life over the course of many universe generations. Such additional fine-tuning may consist of travelling between universes and an afterlife on a distant planet. Second, evolutionary conservation in the evolution of universes in the multiverse provides a declaration why we observe a universe that roughly has the minimal fine-tuning to support intelligent life. (shrink)

According to Minkoswki, Einstein's special theory of relativity reveals that ‘space by itself, and time by itself are doomed to fade away into mere shadows’. But perceptual experience represents objects as instantiating shapes like squareness — properties of ‘space by itself’. Thus, STR seems to threaten the veridicality of shape experience. In response to this worry, some have argued that we should analyze the contents of our spatial experiences on the model of traditional secondary qualities. On this picture—defended in recent (...) work by Chalmers —an experience of squareness just represents whatever property usually causes such experiences. This view salvages the veridicality of shape experience, but leaves the nature of the properties we perceive outside our ken. I argue that such a move is unwarranted: STR is compatible with the idea that shape experience acquaints us with the spatial character of our world. In defending this claim, I propose a view on which shape experience presents familiar Euclidean spatial properties veridically, while implicitly representing those properties as instantiated in a particular manner — namely, relative to our own frame of reference. (shrink)

Our laws of nature and our cosmos appear to be delicately fine-tuned for life to emerge. First, if the initial conditions prevailing immediately after the Big Bang had been ever so slightly different, then the universe would either have recollapsed immediately, or would have expanded far too quickly into a chilling, eternal void. Second, if any one of the fundamental forces of nature had been a tiny bit different in strength, or if the masses of some elementary particles had been (...) a little unlike they are, there would have been no stars and no recognizable chemistry, and hence no Sun, no Earth, no carbon, et cetera. These highly special conditions and numbers suggest some sort of a conspiracy of literally cosmic proportions, which seems rather hard to attribute to chance. Some theologians and religiously oriented scientists and philosophers have taken advantage of this apparent fine-tuning of the clockwork of the universe to revive the scholastic Argument from Design, but also secular thinkers have felt the need to explain fine-tuning, typically by proposing the existence of a `Multiverse', i.e., a vast family of universes existing in parallel, of which ours is merely one, singled out by the `Anthropic Principle' to the effect that it is the only one that can possibly contain observers and hence can be observed. We analyze this issue from a sober perspective. Having reviewed the literature and having added several observations of our own, we conclude that cosmic fine-tuning turns out to support neither Design nor a Multiverse, both of which fail to explain fine-tuning or even to increase its likelihood. In fact, fine-tuning and Design rather seem to be at odds with each other, except when one makes an additional assumption that is practically indistinguishable from Design and hence renders the whole argument circular. Likewise, the inference from fine-tuning to a Multiverse only works if the latter is underwritten by a startling metaphysical hypothesis we consider unwarranted. Instead, we conclude that fine-tuning requires no special explanation at all, since it is not the Universe that is fine-tuned for life, but life that has been fine-tuned to the Universe. (shrink)

The idea that there might be multiple universes with different parameters of nature is often considered an attractive response to the finding that various parameters appear to be delicately fine-tuned for life. The present paper investigates whether the appeal to fine-tuning can legitimately be combined with an appeal to independent empirical evidence for other universes or whether, as suggested by Cory Juhl, combining such appeals inevitably results in illegitimate double counting of the finding that the parameters are right for life. (...) In doing so, the paper takes into account the fact that the parameters' life-friendliness is old evidence for us, which makes Bayesianism's problem of old evidence relevant to Bayesian analysis of its evidential impact. Ultimately, the verdict reached is that the warning of double counting is helpful, but that double counting can in principle be avoided. The paper highlights remaining independent challenges against the fine-tuning argument for the multiverse. (shrink)