• Re: Ex Nihilo Onus Merdae Fit

    In his blog post “Ex Nihilo Onus Merdae Fit” (https://www.richardcarrier.info/archives/468), Richard Carrier argues that the (theistic-friendly) principle ex nihilo nihil fit (“from nothing, nothing comes”) is false. He first describes a possible world where there exists a “state of absolute nothingness.” In this state, the only things that exist are things that are considered logically necessary (with the exception of God), that is, all logically necessary laws, i.e. the laws of logic and mathematics, and – since, as he claims, those laws must exist at some location or at some point in time – a singular point of space(-time) devoid of matter/energy – which isn’t really nothing after all, at least not in the non-referential sense, but let that pass. Carrier then claims that this “state of absolute nothingness” cannot be governed by the law ex nihilo nihil fit, since that law is not itself logically necessary. Finally, he argues (probabilistically) that if there is no such law, then the “state of absolute nothingness” actually causally necessitates an infinite multiverse containing our very own universe. So Carrier is not only arguing that “from nothing, nothing comes” is false, he is arguing that the opposite is true, i.e. “from nothing, everything comes”. I find this to be an intriguing argument, although, as I will show, it is unsound, whichever way you look at it.

    Firstly, I believe that Carrier misconstrues the principle ex nihilo nihil fit. This principle does not imply that a “state of absolute nothingness” is causally inert, for it could well be causally active, as Carrier argues, and ex nihilo nihil fit would still be true. As Wes Morriston has argued, “charitably interpreted, the claim that something can’t come from nothing just is [referring to premise 1 of the Kalam cosmological argument] the claim that nothing [not anything] can come into existence uncaused” (Morriston 2013). This principle is plausible in my opinion because, as William Lane Craig explains, “if things really could come into being uncaused … then it becomes inexplicable why just anything or everything does not come into existence uncaused … given a pure A-Theory of time, according to which only the present exists, every moment of time is a fresh beginning, qualitatively indistinguishable from a first moment of time, for when any moment is present, earlier moments have passed away and do not exist. Thus, if the universe could exist uncaused at a first moment of time, it could exist uncaused at any moment of time. There just does not seem to be any relevant difference. It follows that if the latter is metaphysically impossible, so is the former” (Craig & Sinclair 2009, p. 187). Of course, this presupposes an A-Theory of time, but such a theory is plausible in its own right (Craig 2000a, Craig 2000b).

    Secondly, even if we reinterpret ex nihilo nihil fit to mean what Carrier thinks it means, the argument still fails. To begin with, it is not at all clear that space can exist apart from matter and energy, even a singular point of space(-time). Moreover, why should we accept Carrier’s contention that the law ex nihilo nihil fit, as he interprets it, is not logically necessary? Since these two claims are assumed without argument or evidence, insufficient grounds are provided for Carrier’s conclusion. However, there is a more pressing problem, as I will argue.

    A singular point of space(-time) is either timeless or it is temporal, in which case it either has a beginning or it is past-eternal. But a timeless point of space is impossible (at least if atheism is true) because, as Wes Morriston explains, “the material cause of the universe [in other words, the stuff out of which the universe is made, i.e. that singular point of space] couldn’t be timeless because it is a part or an aspect of the universe, and because every such part or aspect is temporal. The material cause of the universe (if there were one) wouldn’t just disappear after creation. It would remain within the physical universe — as the stuff of which it continues to be “made.” If there were a material cause of the universe, it would necessarily have temporal duration.” (Morriston 2002). So, either the singular point of space(-time) that Carrier has in mind has a beginning or it is past-eternal.

    If the singular point of space(-time) has a beginning, then this raises the question “what caused that singular point of space-time?” – a question which Carrier’s argument does not address. Carrier argues that “[i]f there was absolutely nothing, then (apart from logical necessity) nothing existed to prevent anything from happening or to make any one thing happening more likely than any other thing.” However, there was never a time when space-time did not exist. Therefore, Carrier’s argument does not apply. Since, as I argued above, “nothing [not anything] can come into existence uncaused,” it follows that the singular point of space-time must have a cause and that such a cause must be a being possessing many of the attributes of God (henceforth “God”) – “an uncaused, personal Creator of the universe … who sans the universe is beginningless, changeless, immaterial, timeless, spaceless and enormously powerful” (Craig & Sinclair 2009).

    In his argument, Carrier basically assumes that God does not exist necessarily and hence that he does not exist in the “state of absolute nothingness”. But, we’ve just seen that if this state has a beginning, then it is caused by God. And if it is caused by God, then God exists in the “state of absolute nothingness”. Consequently, the “state of absolute nothingness” cannot be just a singular point of space-time with a beginning. Given that either such a state has a beginning or it is past-eternal (as argued previously), it follows that the “state of absolute nothingness” which Carrier has in mind must be a past-eternal singular point of space.

    Unfortunately for Carrier, it is not possible for a past-eternal singular point of space to exist, at least not on a relational theory of time. On a relational theory of time, a temporal series of past moments requires a temporal series of past events (or changes). But there cannot be a temporal series of past events (or changes) in a singular (zero dimensional) point of space.

    In conclusion, Carrier’s argument, while interesting, does not succeed in showing that the principle ex nihilo nihil fit (“from nothing, nothing comes”), however you interpret it, is false, let alone that “from nothing (a “state of absolute nothingness”), everything comes”. In fact, as I showed, ex nihilo nihil fit, as traditionally understood, is a very plausible principle.

    Now, in response to my rebuttal of his argument, Carrier might produce an undercutting defeater for my belief that “nothing [not anything] can come into existence uncaused.” Would Carrier’s “Ex Nihilo Onus Merdae Fit” argument then show that the principle ex nihilo nihil fit, however you interpret it, is false? Not really. He would still have to produce a rebutting defeater for my belief that “nothing [not anything] can come into existence uncaused,” that is the case even if one grants Carrier’s interpretation of the principle ex nihilo nihil fit, for if the singular point of space(-time) in his argument has a beginning (since it cannot be timeless nor past-eternal), then the question as to whether God caused it and, hence, whether God exists at the same time as the singular point of space-time remains unanswered.

    In summary, Carrier argues that a singular point of space-time, plus everything that is logically necessary (except god), plus nothing else, entails the existence of an infinite multiverse containing our very universe. In this post, I have shown that for Carrier’s argument to work, the singular point of space cannot be timeless or past-eternal. Therefore, it must have a beginning. However, it cannot have a beginning, for if it had a beginning, then something like God would exist, and if something like God would exist, then it would not be the case that there exists a singular point of space-time, plus everything that is logically necessary (except god), plus nothing else. Carrier presumably wants to avoid postulating the existence of God, so he would not be happy to introduce God into reality.

    References:

    Craig, W. L. (2000a). The Tensed Theory of Time: A Critical Examination. Dordrecht: Kluwer Academic Publishers.

    Craig, W. L. (2000b). The Tenseless Theory of Time: A Critical Examination. Dordrecht: Kluwer Academic Publishers.

    Craig, W. L., & Sinclair, J. (2009). The Kalam Cosmological Argument. In W. L. Craig & J. P. Moreland (Eds.), The Blackwell Companion to Natural Theology (pp. 101-201). Oxford: Wiley-Blackwell.

    Morriston, W. (2002). Creation ex Nihilo and the Big Bang. Philo, 5 (9): 23-33.

    Morriston, W. (2013). Doubts about the kalam cosmological argument. In J. P. Moreland, C. Meister & K. A. Sweis (Eds.), Debating Christian Theism (pp. 20-32). Oxford: Oxford University Press.

  • A Simple Argument Against Physicalism

    I want to start by saying that I haven’t exhaustively surveyed the literature on physicalism, so the following argument probably isn’t new (relevant links to the literature would be appreciated). Physicalism is the philosophical view that everything is physical. The problem with physicalism is that it seems that the process of thinking and reasoning disproves it. When the content of one idea elicits another idea, when we move from one step to another in a valid argument, it seems that it is the thinking and reasoning that causes the neural processing, not the other way around. How could the neural processing cause the logical sequence of elicited ideas? I accept that the content of one idea can be correlated with a neural process, but what I deny is that a train of thought where the content of one idea or logical step leads to another idea or logical step can be caused by a neural process. Neural processes cannot make logical inferences based on previously elicited mental content. It’s the content of the ideas that is eliciting further ideas, as when one has a train of thought. This process causes the neural processing, not the other way around.

  • Should You Invest in Life-Extension Medical Research?

    The right to choose to live or to die is the most fundamental right there is; conversely, the duty to give others that opportunity to the best of our ability is the most fundamental duty there is.

    Aubrey de Grey

    Should you invest in healthy life-extension medical research? Aubrey de Grey thinks that you should. De Grey is a biomedical gerontologist and Co-founder of SENS Research Foundation, a 501(c)(3) public charity that funds biomedical research into “regenerative medicine to repair the damage underlying the diseases of aging” (About SENS Research Foundation, n.d.). For the past 20 years or so, de Grey has been researching and promoting regenerative medicine solutions to the problem of aging.

    In 2007, de Grey published the book Ending Aging: The Rejuvenation Breakthroughs that Could Reverse Human Aging in Our Lifetime. Ending Aging details how age-related decline and illness could be reversed in the near future if sufficient investments were made in what de Grey calls “SENS” research. SENS (or “Strategies for Engineered Negligible Senescence”) refers to a set of regenerative medicine approaches developed by de Grey which directly target age-related tissue damage at the microscopic level. While some gerontologists believe that the maximum lifespan can be extended through metabolic interventions (Olshansky, 2017; Zorn, 2018), de Grey thinks that metabolism is too complex to be effectively controlled for the foreseeable future. Just as we can keep vintage cars looking and operating like new by repairing broken parts or replacing them with new ones, de Grey points out that we can keep humans in a youthful state indefinitely by periodically removing or repairing damaged tissues at the cellular and molecular levels.

    While de Grey’s “SENS” proposal to extend healthy human life remains controversial among gerontologists, SENS Research Foundation’s 30-member expert Advisory Board has endorsed de Grey’s conclusions that,

    Recent biotechnological progress indicates that many aspects of aging may indeed be effectively treatable by regenerative medicine in the foreseeable future. We cannot yet know whether all aspects will be, but extensive scrutiny has failed to identify any definite exceptions. Therefore, at this point there is a significant chance that such therapies would postpone age-related decline by several years, if not more, which constitutes a clear case for allocating significant resources to the attempt to develop those therapies. (SENS Research Foundation Research Advisory Board, n.d.)

    On this basis, de Grey has argued that Investments in regenerative medicine to extend healthy human life are morally imperative. One of his arguments can be put as follows:

    What gives us the right to decide for future generations whether they should or should not live healthily past the age of 120 years? If we refrain from investing in healthy life-extension technologies today because of moral concerns, then we are in effect denying future generations (our children and grandchildren) the right to live healthy lives past our current maximum lifespan. What is considered moral today might be considered loathsome tomorrow, either because circumstances have changed or because values have shifted (Schwitzgebel, 2018). So if we decide today not to implement those technologies because of overriding moral concerns, then we are rationally entitled not to do so, but what we are not rationally entitled to do is to prevent future generations from benefiting from those technologies should they deem them morally obligatory. Therefore, we can have a reasoned debate about whether it would be moral to implement healthy life-extension technologies today (and de Grey has forcefully argued that it is morally obligatory to do so), but what we cannot rationally refrain from doing is investing in healthy life-extension technologies today for the benefit of future generations (our children and grandchildren) should they deem those technologies morally necessary.[1]

    This suggests a more general principle of ethics and rational choice: Values and preferences may change over time. Therefore, to the extent that no current values or preferences are violated, a robust decision rule should leave open as many choice opportunities as possible to accommodate future changes in values or preferences.

    Bibliography

    About SENS Research Foundation (n.d.). SENS Research Foundation. Retrieved April 9, 2021, from http://www.sens.org/about

    De Grey, A., & Rae, M. (2007). Ending Aging: The Rejuvenation Breakthroughs That Could Reverse Human Aging in Our Lifetime. New York: St. Martin’s Press.

    Olshansky, S. J. (2017). Is Life Extension Today a Faustian Bargain? Frontiers in Medicine, 4(215), 1–3. https://dx.doi.org/10.3389%2Ffmed.2017.00215

    SENS Research Foundation Research Advisory Board (n.d.). SENS Research Foundation. Retrieved April 9, 2021, from http://www.sens.org/about/leadership/research-advisory-board

    Schwitzgebel, E. (2018, June 30). Will Future Generations Find Us Especially Morally Loathsome? The Splintered Mind. https://schwitzsplinters.blogspot.com/2018/06/will-future-generations-find-us.html

    Wareham, C. S. (2018). What is the ethics of ageing? Journal of Medical Ethics, 44, 128–132. http://dx.doi.org/10.1136/medethics-2017-104374

    Zorn, E. (2018, July 13). A 150-year-old human? Neither side is folding in The Great Longevity Wager. Chicago Tribune. http://www.chicagotribune.com/news/opinion/zorn/ct-perspec-zorn-longevity-aging-olshansky-austad-20180715-story.html


    [1] For a helpful introduction to the ethics of ageing, see Wareham (2018).

  • How to Make Rational Choices

    Unless there are overriding moral objections, one should make instrumentally rational choices—choices that best serve one’s ends full stop. Expected utility (EU) theory is generally accepted as a normative theory of (instrumentally) rational choice under risk. EU theory advises agents to rank their choice options (from least to most choiceworthy) according to their EU, where the EU of an option is a probability-weighted sum of each of its possible utilities.[1] According to Martin Peterson, today, nearly all decision theorists accept EU theory (Peterson, 2017, p. 66). As such, as long as that is the case, laypersons with respect to decision theory will be rationally required to accept EU theory.

    Philosopher Johan Gustafsson has argued that choice options in a decision problem should be construed as sets of acts such that one could jointly intentionally perform, at any time t, all the acts in the set, but no additional acts (Gustafsson, 2014). One of the reasons given by Gustafsson is that if one construes choice options as individual acts, then one runs into the Problem of act versions (Bergström, 1966; Castaneda, 1968). Consider the following example:

    It is raining outside, but Ann will feel invigorated if she takes a brisk walk around the block (10 utiles), more so than if she stays inside (2 utiles). However, Ann has an injured toenail which causes her a great deal of pain when she tries to walk with her rain boots on. She will therefore experience a great deal of pain if she goes out for a walk wearing her rain boots (–30 utiles), more so than if she stays inside wearing her rain boots (–2 utiles). Luckily, Ann has a very comfortable pair of shoes which do not cause her any pain. However, there is a problem: it is raining very hard and her feet will get soaked. Ann will experience considerable discomfort if she goes out for a walk not wearing her rain boots (–15 utiles), more so than if she stays inside not wearing her rain boots (0 utiles).

    Let us suppose that Ann assigns probability 1 to the state of the world as described above. Although the utility of the act ‘Ann stays inside’ is lower than that of the act ‘Ann goes out for a walk’, the utility of at least one version of the act ‘Ann stays inside’—that is, ‘Ann stays inside and does not wear her rain boots’ (2 + 0 = 2 utiles)—is greater than the utility of all versions of the act ‘Ann goes out for a walk’—that is, ‘Ann goes out for a walk and wears her rain boots’ (10 + –30 = –20 utiles) and ‘Ann goes out for a walk and does not wear her rain boots’ (10 + –15 = –5 utiles). Thus, intuitively, Ann should stay inside. However, if choice options are construed as individual acts, then EU theory counsels Ann not to stay inside, but instead to go out for a walk.

    Therefore, to be intuitively plausible, EU theory should be minimally cashed out as follows:[2]

    For any agent, S, faced with any decision under certainty or under risk and for any number of mutually exclusive and jointly exhaustive options, or sets of acts, a, b, c, d and e, such that, for each set, S could jointly intentionally perform, at any time, t, all the acts in the set, but no additional acts,

    • a is more choiceworthy than b, for S, at t, if and only if the EU of S jointly intentionally performing a at t is greater than the EU of S jointly intentionally performing b at t, and
    • a is just as choiceworthy as b, for S, at t, if and only if the EU of S jointly intentionally performing a at t is equal to the EU of S jointly intentionally performing b at t.

    This implies the following derivative decision rule for individual acts:[3]

    For any agent, S, faced with any decision under certainty or under risk and for any two mutually exclusive acts, a and b,

    • a is more choiceworthy than b, for S, at any time, t, if and only if a is logically entailed by every set of acts such that, for each set, S could jointly intentionally perform, at t, all the acts in the set, but no additional acts and such that, in accordance with EU theory, the set of acts would be more choiceworthy for S, at t than each set of acts such that S could jointly intentionally perform, at t, all the acts in the set, but no additional acts and such that the set of acts logically entails b, and
    • a is just as choiceworthy as b, for S, at any time, t, if and only if a is not more choiceworthy than b, and a is logically entailed by every set of acts such that, for each set, S could jointly intentionally perform, at t, all the acts in the set, but no additional acts and such that, in accordance with EU theory, the set of acts would not be less choiceworthy for S, at t than each set of acts such that S could jointly intentionally perform, at t, all the acts in the set, but no additional acts and such that the set of acts logically entails b.

    Bibliography

    Bergström, L. (1966). The Alternatives and Consequences of Actions. Stockholm: Almqvist & Wiksell.

    Castaneda, H.-N. (1968). A Problem for Utilitarianism. Analysis, 28(4), 141–142. https://doi.org/10.1093/analys/28.4.141

    Gintis, H. (2018). Rational Choice Explained and Defended. In G. Bronner & F. Di Iorio (Eds.), The Mystery of Rationality: Mind, Beliefs and the Social Sciences (pp. 95–114). Springer. https://doi.org/10.1007/978-3-319-94028-1_8

    Gustafsson, J. E. (2014). Combinative Consequentialism and the Problem of Act Versions. Philosophical Studies, 167(3), 585–596. https://doi.org/10.1007/s11098-013-0114-x

    Peterson, M. (2017). An Introduction to Decision Theory. Cambridge University Press. https://doi.org/10.1017/9781316585061


    [1] For a defense of EU theory, see Gintis (2018).

    [2] Inspired by Gustafsson (pp. 593–594).

    [3] Inspired by Gustafsson (p. 595).

  • Should You Be Skeptical of Climate Change: Letter to a Climate Skeptic

    This is a short letter in response to a Reddit post on climate change skepticism (see below):

    Until recently, I never read much about climate change other than standard newspaper stuff. I think I have heard most of the arguments for it. I’ve also heard people say stuff like “everyone who actually studies/is an expert on climate change agrees”. Well, Judith Curry studies it and doesn’t. As I read through this presentation, it seems balanced and well thought out. In fact, searching through “climate sceptic” sites on the web, I find surprisingly sensible-seeming people with logical arguments and data references. This [Curry, 2018] walkthrough is a good example. So can anyone tell me; am I missing something obvious? Why are the arguments for climate scepticism wrong?

    Any feedback is appreciated (u/HCAndersAnd, 2018).

    Dear Skeptic,

    I think that you are honest and fair-minded. Your skepticism of consensus climate change science is understandable, but it is misplaced. Since you are not an expert on the science of climate change, you are rationally required to believe consensus climate change science.[1] But you might ask, “Why should I believe that the climate science claims made by proponents of climate change mitigation are consensus climate science?”

    Signatory governments to the Paris climate change agreement base their support for climate change mitigation on the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) (The Paris Agreement, n.d.).[2] A key finding of the AR5 is quoted below:

    Projections of changes in the climate system are made using a hierarchy of climate models ranging from simple climate models, to models of intermediate complexity, to comprehensive climate models, and Earth System Models. These models simulate changes based on a set of scenarios of anthropogenic forcings. […]

    Relative to the average from year 1850 to 1900, global surface temperature change by the end of the 21st century is projected to likely exceed 1.5°C for RCP4.5, RCP6.0 and RCP8.5 (high confidence). Warming is likely to exceed 2°C for RCP6.0 and RCP8.5 (high confidence), more likely than not to exceed 2°C for RCP4.5 (high confidence), but unlikely to exceed 2°C for RCP2.6 (medium confidence). Warming is unlikely to exceed 4°C for RCP2.6, RCP4.5 and RCP6.0 (high confidence) and is about as likely as not to exceed 4°C for RCP8.5 (medium confidence). {12.4} (IPCC, 2013, p. 18)

    You should believe that the above statement (call it X) is consensus climate change science because (i) X is clear and unambiguous and (ii) X is quoted from the work of the IPCC, and there is a consensus among recognized organizations of experts with expertise in climate science that “the work of the IPCC represents the consensus of the international scientific community on climate change science.” (The Science of Climate Change, 2001, p. 1261)[3]

    Suppose however that X was consensus climate science at the moment of publication of the AR5, but X is no longer consensus climate science, and you have polling or other unequivocal evidence to support this. It then follows that (i) you should disbelieve X if consensus temperature projections have shifted since publication of the AR5 or (ii) you should withhold belief about X if there are no longer any consensus temperature projections and no such projections are believed by even the majority of climate scientists.

    Suppose instead that X was not consensus climate science at the moment of publication of the AR5 (and that X is not currently believed by even the majority of climate scientists). This would be the most significant and egregious failure of science communication in history. All the climate scientists who were involved in signing off on X’s wording would have experienced a lapse or would have engaged in deception. This would have happened in a report, the AR5’s Summary for Policymakers, that is designed to guide laypersons in making informed policy decisions on climate change. This is very improbable.

    Therefore, unless you have polling or other unequivocal evidence that X is no longer consensus climate science, the likelihood that X is currently consensus climate science is significantly greater than the likelihood that X is not currently consensus climate science. And so, it is rational to believe that X is consensus climate science.

    In conclusion, if you were a dissenting expert on the science of climate change—that is, if you regarded yourself as such or if you were a practicing climate scientist who disagreed with the conclusions of your peers on climate change science—then you would be entitled to your own view on those conclusions. But, judging from your question, you are clearly not a dissenting expert. As such, I hope to have convinced you that, unless and until you become an expert, you are rationally required to believe the statement quoted above from the IPCC’s AR5.[4]

    Bibliography

    Coady, D., & Corry, R. (2013). The Climate Change Debate: An Epistemic and Ethical Enquiry. London: Palgrave Macmillan. https://doi.org/10.1057/9781137326287

    Curry, J. (2018, June 12). The Debate: My Presentation. Climate Etc. https://web.archive.org/web/20180630062836/https://judithcurry.com/2018/06/12/the-debate-mann-titley-moore-curry/

    Gao, Y., Gao, X., & Zhang, X. (2017). The 2 °C Global Temperature Target and the Evolution of the Long-Term Goal of Addressing Climate Change—From the United Nations Framework Convention on Climate Change to the Paris Agreement. Engineering, 3(2), 272–278. https://doi.org/10.1016/J.ENG.2017.01.022

    IPCC (2013). Summary for Policymakers. InT. F. Stocker, D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex & P. M. Midgley(Eds.), Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge: Cambridge University Press. http://www.climatechange2013.org/images/report/WG1AR5_SPM_FINAL.pdf#page=18

    Kaulbars, M. (2010, June 14). Letter To A Climate ‘Skeptic’. News Junkie Post. https://web.archive.org/web/20180630073421/http:/newsjunkiepost.com/2010/06/14/letter-to-a-climate-%E2%80%9Cskeptic%E2%80%9D/

    Morrison, D. (2011). Letter to Climate Skeptics. Skeptic, 16(2), 10. http://go.galegroup.com/ps/anonymous?id=GALE%7CA252289589

    Newman, S, (2016, July 1). An open letter to climate change sceptics. 1 Million Women. https://web.archive.org/web/20180423160439/https:/www.1millionwomen.com.au/blog/open-letter-climate-change-sceptics/

    Scientific consensus: Earth’s climate is warming. (n.d.) Global Climate Change: Vital Signs of the Planet. Earth Science Communications Team at NASA’s Jet Propulsion Laboratory. Retrieved April 8, 2021, from https://climate.nasa.gov/scientific-consensus/

    The Paris Agreement (n.d.). United Nations Climate Change. Retrieved April 8, 2021, from https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement

    The Science of Climate Change (2001). Science, 292(5520), 1261. https://doi.org/10.1126/science.292.5520.1261

    u/HCAndersAnd (2018, June 12). What is wrong with these arguments? Reddit (r/climatechange). Retrieved April 8, 2021, from https://www.reddit.com/r/climatechange/comments/8qnq31/what_is_wrong_with_these_arguments/


    [1] For any proposition, p, a layperson with respect to p is rationally required to believe p if and only if p is believed by the majority of experts on p. See Coady and Corry (2013).

    [2] Gao, Gao, and Zhang (2017) note that,

    In 2008–2014, the IPCC’s Fifth Assessment Report (AR5) made a comprehensive assessment of the climate system change, risks, emission budget, and mitigation pathway choice of 2°C global warming on the basis of the research results available. After scientific assessment and a series of political pushes, one of the three goals reached at the 2015 Paris Climate Change Conference was stated as “Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels” [3].

    [3] See also Scientific consensus: Earth’s climate is warming (n.d.).

    [4] I noted three earlier uses of this “Letter to a climate skeptic” format: Kaulbars, 2010; Morrison, 2011; and Newman, 2016.

  • How to Acquire Rational Belief Attitudes

    How should a layperson think (or form belief attitudes) about any given statement? Is it enough to research reliable sources and use logical, unbiased thinking? In Chapter 1, I will argue that it is not and that a layperson should instead defer to the majority testimony of experts on that statement, if there are any experts on that statement.

    For any statement (or proposition), p, there are three possible belief attitudes (or doxastic attitudes, in technical jargon) toward p: to believe p (which is consistent with having a range of degrees of confidence in p), to disbelieve p (to believe that p is false), and to withhold belief about p (to withhold belief about whether p is true or false).

    Doxastic attitudes may not be directly voluntary, but they can be informed by guiding principles that are sufficiently prima facie plausible or evidenced. Consider the following prima facie plausible principle: Unless there are overriding moral objections, one should form epistemically rational doxastic attitudes—that is, doxastic attitudes that best serve one’s epistemic ends, namely those of acquiring true beliefs and avoiding false beliefs to some respective extent.

    Generally, when choosing between different courses of action, with a view to achieving one’s ends, false beliefs are undesirable more so than true beliefs are desirable. One error or miscalculation is often enough to undermine such a decision. Nevertheless, true beliefs are still obviously essential to choosing the best courses of action in pursuit of one’s goals. Therefore, one should aim to maximize one’s subjective chances of holding a favorable ratio of true beliefs to false beliefs (Alston, 1985), rather than the highest absolute number of true beliefs or the lowest absolute number of false beliefs.

    It follows that unless there are overriding moral objections, one should acquire epistemically rational doxastic attitudes—that is, doxastic attitudes that maximize one’s subjective chances of holding a favorable ratio of true beliefs to false beliefs.

    Now, avoiding fallacies, mitigating one’s cognitive biases, and relying on trustworthy sources of information are the most commonly talked about ways of promoting truth-conducive thinking (or, in other words, acquiring epistemically rational doxastic attitudes). But for any given proposition, unless one is an expert on that proposition, there are ways of thinking about that proposition that are considerably more truth-conducive (or epistemically rational) but rarely if ever discussed outside of specialist academic circles—namely, following the rules of epistemic rationality that govern how laypeople should learn from the testimony of experts.

    There are cases of credentialed experts defending fringe claims in reliable sources, such as academic journals, without apparently committing any logical fallacies and without showing any overt signs of bias (Curry, 2011; Lemonick, 2010). This is to be expected in the sciences and in philosophy, where progress often requires that individual scientists and philosophers challenge mainstream or even consensus views.

    Laypeople who have learned how to discern logical fallacies, cognitive biases, as well as reputable and disreputable sources of information will be poorly equipped to rationally assess the statements made by those credentialed experts unless and until these laypeople are made acutely aware of the rules of epistemic rationality that govern how they should learn from the testimony of experts—that is, how they should adjust their own doxastic attitudes in light of what doxastic attitudes experts hold.

    These rules of epistemic rationality can be summarised as follows: For any proposition, p, a layperson with respect to p is rationally required to believe p if and only if p is believed by the majority of experts on p. There are exceptions to the rule. See Lahno (2014). See also Coady (2012), Goldman (2001), and Huemer (2005). Of course, there is, in principle, nothing stopping a layperson from becoming an expert on p. In that case, there are several alternative belief-forming methodologies available to him or her in the published literature (Matheson, 2015).

    Anyone can be an expert on any given proposition, regardless of their academic or professional credentials, provided that they have studied or researched sufficiently thoroughly and impartially the evidence that bears on that proposition (Croce, 2019). The key word here is “sufficiently”. Given the Dunning–Kruger effect (i.e., “difficulties in recognizing one’s own incompetence lead to inflated self-assessments”[1]), those who lack the academic or professional credentials of credentialed experts should exercise caution in self-identifying as experts, and others should also exercise caution in identifying them as experts.

    In the case of philosophical propositions, and especially ethical and religious propositions, it is arguable whether there are any genuine experts on those propositions (De Cruz, 2018; Frances, 2018; Matheson, McElreath, & Nobis, 2018).

     

    Bibliography

    Alston, W. (1985). Concepts of epistemic justification. The Monist, 68(1), 57–89. https://doi.org/10.5840/monist198568116

    Coady, D. (2012). What to Believe Now: Applying Epistemology to Contemporary Issues. Chichester: Wiley-Blackwell.

    Croce, M. (2019). On What it Takes to be an Expert. The Philosophical Quarterly, 69(274), 1–21. https://doi.org/10.1093/pq/pqy044

    Curry, J. (2011). Reasoning about climate uncertainty. Climatic Change, 108, 723–732. https://doi.org/10.1007/s10584-011-0180-z

    Curtis, G. N. (n.d.). The Fallacy Files. Retrieved April 8, 2021, from http://www.fallacyfiles.org/

    De Cruz, H. (2018). Religious Disagreement. Cambridge: Cambridge University Press.

    Dowden, B. (n.d.). Fallacies. The Internet Encyclopedia of Philosophy. Retrieved April 8, 2021, from https://www.iep.utm.edu/fallacy/

    Dunning, D. (2014). We are all confident idiots. Pacific Standard, 7(6), 46–54. https://psmag.com/social-justice/confident-idiots-92793

    Frances, B. (2018). Philosophical Expertise. In D. Coady & J. Chase (Eds.), The Routledge Handbook of Applied Epistemology (Routledge Handbooks in Philosophy) (pp. 297–306). Routledge. https://doi.org/10.4324/9781315679099

    Goldman, A. (2001). Experts: Which Ones Should You Trust? Philosophy and Phenomenological Research, 63(1), 85–110. https://doi.org/10.1111/j.1933-1592.2001.tb00093.x

    Huemer, M. (2005). Is Critical Thinking Epistemically Responsible? Metaphilosophy, 36(4), 522–531. https://doi.org/10.1111/j.1467-9973.2005.00388.x

    Is My Source Credible? (n.d.). University of Maryland University College. Retrieved April 8, 2021, from https://sites.umuc.edu/library/libhow/credibility.cfm

    Kruger, J., & Dunning, D. (1999). Unskilled and unaware of it: How difficulties in recognizing one’s own incompetence lead to inflated self-assessments. Journal of Personality and Social Psychology, 77(6), 1121–1134. https://doi.org/10.1037/0022-3514.77.6.1121

    Lahno, B. (2014). Challenging the majority rule in matters of truth. Erasmus Journal for Philosophy and Economics, 7(2), 54–72. https://doi.org/10.23941/ejpe.v7i2.167

    Lemonick, M. D. (November 1, 2010). Climate heretic: Judith Curry turns on her colleagues. Nature. https://doi.org/10.1038/news.2010.577

    Matheson, J. (2015). Disagreement and Epistemic Peers. Oxford Handbooks Online. http://dx.doi.org/10.1093/oxfordhb/9780199935314.013.13

    Matheson, J., McElreath, S., & Nobis, N. (2018). Moral Experts, Deference & Disagreement. In J. C. Watson & L. K. Guidry-Grimes (Eds.), Moral Expertise: New Essays from Theoretical and Clinical Bioethics (pp. 87–106). Springer. https://doi.org/10.1007/978-3-319-92759-6_5


    [1] Kruger & Dunning, 1999.

  • A Companion to Rationality

    It has always appalled me that really bright scientists almost all work in the most competitive fields, the ones in which they are making the least difference. In other words, if they were hit by a truck, the same discovery would be made by somebody else about 10 minutes later.

    Aubrey de Grey

    To make instrumentally rational choices involves choosing courses of action that best serve one’s ends. As a good example, one’s chances of having a positive impact on the world are significantly greater if one focuses one’s efforts on solving the world’s biggest, most urgent problems than if one focuses one’s efforts on solving comparatively small, non-urgent problems that will not ultimately matter in the long run if the biggest, most urgent problems are left unsolved. Therefore, if one’s goal is to make a difference in the world, then it is simply not rational to focus one’s efforts on solving comparatively small, non-urgent problems.

    It is true that functioning societies do need people working on comparatively small day-to-day problems. But a shortage of people working on comparatively small day-to-day problems is itself a big urgent problem and so, something that one would need to factor into any rational decision about where to focus one’s efforts.

    Moreover, it does not require an exceptionally intelligent person to survey the literature on the various problems that we may be facing and to arrive at a correct assessment of what problems are the biggest and most urgent and what problems are comparatively small and non-urgent. To adopt rational belief attitudes is to adopt belief attitudes (i.e., to believe, to disbelieve or to withhold belief) that best serve one’s epistemic ends, namely those of acquiring true beliefs and avoiding false beliefs. So, provided that one’s methodology for acquiring rational belief attitudes is robust, then there is surely a reasonably approachable threshold of analysis and synthesis beyond which more sophisticated analysis and synthesis will not likely yield a more correct assessment of what problems are the biggest and most urgent and what problems are comparatively small and non-urgent.

    We face today an unprecedented number of big urgent problems. With those problems in mind, in this blog, I will supply readers with a robust methodology for acquiring rational belief attitudes and making rational decisions. Readers will then be better equipped to identify and solve the world’s biggest, most pressing problems.

     

    Bibliography

     

    Gates, B., & Gates, M. (n.d.). Annual Letters From Bill & Melinda Gates. Bill & Melinda Gates Foundation. Retrieved April 8, 2021, from https://www.gatesfoundation.org/Ideas/Annual%20Letters

    MacAskill, W. (2015). Doing Good Better: How Effective Altruism Can Help You Make a Difference. New York: Avery. http://www.effectivealtruism.org/doing-good-better

    Singer, P. (2010). The Life You Can Save: How to Do Your Part to End World Poverty. New York: Random House Trade Paperbacks, https://www.thelifeyoucansave.org/the-book/

    Singer, P.(2015). The Most Good You Can Do: How Effective Altruism is Changing Ideas about Living Ethically. Yale University Press. Todd, B. J.(2016). 80,000 Hours: Find a fulfilling career that does good. CreateSpace. https://80000hours.org/book/