Archives For counterfactuals

Author Information: Jonathan Matheson & Valerie Joly Chock, University of North Florida,

Matheson, Jonathan; Valerie Joly Chock. “Knowledge and Entailment: A Review of Jessica Brown’s Fallibilism: Evidence and Knowledge.” Social Epistemology Review and Reply Collective 7, no. 10 (2018): 55-58.

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Jessica Brown’s Fallibilism is an exemplary piece of analytic philosophy. In it, Brown engages a number of significant debates in contemporary epistemology with the aim of making a case for fallibilism about knowledge. The book is divided into two halves. In the first half (ch. 1-4), Brown raises a number of challenges to infallibilism. In the second half (ch. 5-8), Brown responds to challenges to fallibilism. Brown’s overall argument is that since fallibilism is more intuitively plausible than infallibilism, and since it fares no worse in terms of responding to the main objections, we should endorse fallibilism.

What Is Fallibilism?

In the introductory chapter, Brown distinguishes between fallibilism and infallibilism. According to her, infallibilism is the claim that one knows that p only if one’s evidence entails p, whereas fallibilism denies this. Brown settles on this definition after having examined some motivation and objections to other plausible definitions of infallibilism. With these definitions in hand, the chapter turns to examine some motivation for fallibilism and infallibilism.

Brown then argues that infallibilists face a trilemma: skepticism, shifty views of knowledge, or generous accounts of knowledge. Put differently, infallibilists must either reject that we know a great deal of what we think we know (since our evidence rarely seems to entail what we take ourselves to know), embrace a view about knowledge where the standards for knowledge, or knowledge ascriptions, vary with context, or include states of the world as part of our evidence. Brown notes that her focus is on non-skeptical infallibilist accounts, and explains why she restricts her attention in the remainder of the book to infallibilist views with generous conception of evidence.

In chapter 2, Brown lays the groundwork for her argument against infallibilism by demonstrating some commitments of non-skeptical infallibilists. In order to avoid skepticism, infallibilists must show that we have evidence that entails what we know. In order to do so, they must commit to certain claims regarding the nature of evidence and evidential support.

Brown argues that non-factive accounts of evidence are not suitable for defending infallibilism, and that infallibilists must embrace an externalist, factive account of evidence on which knowing that p is sufficient for p to be part of one’s evidence. That is, infallibilists need to endorse Factivity (p is evidence only if p is true) and the Sufficiency of knowledge for evidence (if one knows that p, then p is part of one’s evidence).

However, Brown argues, this is insufficient for infallibilists to avoid skepticism in cases of knowledge by testimony, inference to the best explanation, and enumerative induction. In addition, infallibilists are committed to the claim that if one knows p, then p is part of one’s evidence for p (the Sufficiency of knowledge for self-support thesis).

Sufficiency of Knowledge to Support Itself

Chapter 3 examines the Sufficiency of knowledge for self-support in more detail. Brown begins by examining how the infallibilist may motivate this thesis by appealing to a probabilistic account of evidential support. If probability raisers are evidence, then there is some reason to think that every proposition is evidence for itself.

The main problem for the thesis surrounds the infelicity of citing p as evidence for p. In the bulk of the chapter, Brown examines how the infallibilist may account for this infelicity by appealing to pragmatic explanations, conversational norms, or an error theory. Finding each of these explanations insufficient to explain the infelicity here, Brown concludes that the infallibilist’s commitment to the Sufficiency of knowledge for self-support thesis is indeed problematic.

Brown takes on the infallibilists’ conception of evidence in Chapter 4. As mentioned above, the infallibilist is committed to a factive account of evidence, where knowledge suffices for evidence. The central problem here is that such an account has it that intuitively equally justified agents (one in a good case and one in a bad case) are not in fact equally justified.

Brown then examines the ‘excuse maneuver’, which claims that the subject in the bad case is unjustified yet blameless in their belief, and the original intuition confuses these assessments. The excuse maneuver relies on the claim that knowledge is the norm of belief. Brown argues that the knowledge norm fails to provide comparative evaluations of epistemic positions where subjects are intuitively more or less justified, and fails to give an adequate account of propositional justification when the target proposition is not believed. In addition, Brown argues that extant accounts of what would provide the subject in the bad case with an excuse are all insufficient.

In Chapter 5 the book turns to defending fallibilism. The first challenge to fallibilism that Brown examines concerns closure. Fallibilism presents a threat to multi-premise closure since one could meet the threshold for knowledge regarding each individual premise, yet fail to meet it regarding the conclusion. Brown argues that giving up on closure is no cost to fallibilists since closure ought to be rejected on independent grounds having to do with defeat.

A subject can know the premises and deduce the conclusion from them, yet have a defeater (undercutting or rebutting) that prevents the subject from knowing the conclusion. Brown then defends such defeat counterexamples to closure from a number of recent objections to the very notion of defeat.

Chapter 6 focuses on undermining defeat and recent challenges that come to it from ‘level-splitting’ views. According to level-splitting views, rational akrasia is possible—i.e., it is possible to be rational in simultaneously believing both p and that your evidence does not support p. Brown argues that level-splitting views face problems when applied to theoretical and practical reasoning. She then examines and rejects attempts to respond to these objections to level-splitting views.

Brown considers objections to fallibilism from practical reasoning and the infelicity of concessive knowledge attributions in Chapter 7. She argues that these challenges are not limited to fallibilism but that they also present a problem for infallibilism. In particular, Brown examines how (fallibilist or infallibilist) non-skeptical views have difficulty accommodating the knowledge norm for practical reasoning (KNPR) in high-stakes cases.

She considers two possible responses: to reject KNPR or to maintain KNPR by means of explain-away maneuvers. Brown claims that one’s response is related to the notion of probability one takes as relevant to practical reasoning. According to her, fallibilists and infallibilists tend to respond differently to the challenge from practical reasoning because they adopt different views of probability.

However, Brown argues, both responses to the challenge are in principle available to each because it is compatible with their positions to adopt the alternative view of probability. Thus, Brown concludes that practical reasoning and concessive knowledge attributions do not provide reasons to prefer infallibilism over fallibilism, or vice versa.

Keen Focus, Insightful Eyes

Fallibilism is an exemplary piece of analytic philosophy. Brown is characteristically clear and accessible throughout. This book will be very much enjoyed by anyone interested in epistemology. Brown makes significant contributions to contemporary debates, making this a must read for anyone engaged in these epistemological issues. It is difficult to find much to resist in this book.

The arguments do not overstep and the central thesis is both narrow and modest. It’s worth emphasizing here that Brown does not argue that fallibilism is preferable to infallibilism tout court, but only that it is preferable to a very particular kind of infallibilism: non-skeptical, non-shifty infallibilism.  So, while the arguments are quite strong, the target is more narrow.

One of the central arguments against fallibilism that Brown considers concerns closure. While she distinguishes multi-premise closure from single-premise closure, the problems for fallibilism concern only the former, which she formulates as follows:

Necessarily, if S knows p1-n, competently deduces, and thereby comes to believe q, while retaining her knowledge of p1-n throughout, then S knows q. (101)

The fallibilist threshold condition is that knowledge that p requires that the probability of p on one’s evidence be greater than some threshold less than 1. This threshold condition generates counterexamples to multiple-premise closure in which S fails to know a proposition entailed by other propositions she knows. Where S’s evidence for each premise gives them a probability that meets the threshold, S knows each of the premises.

If together these premises entail q, then S knows premises p1-n that jointly entail conclusion q. The problem is that S knowing the premises in this way is compatible with the probability of the conclusion on S’s evidence not meeting the threshold. Thus, this presents possibility for counterexamples to closure and a problem for fallibilism.

As the argument goes, fallibilists must deny closure and this is a significant cost. Brown’s reply is to soften the consequence of denying closure by arguing that it is implausible due to alternative (and independent) reasons concerning defeat. Brown’s idea is that closure gives no reason to reject fallibilism, or favor infallibilism, given that defeat rules out closure in a way that is independent of the fallibilism-infallibilism debate.

After laying out her response, Brown moves on to consider and reply to objections concerning the legitimacy of defeat itself. She ultimately focuses on defending defeat against such objections and ignores other responses that may be available to fallibilists when dealing with this problem. Brown, though, is perhaps a little too quick to give up on closure.

Consider the following alternative framing of closure:

If S knows [p and p entails q] and believes q as the result of a competent deduction from that knowledge, then S knows q.

So understood, when there are multiple premises, closure only applies when the subject knows the conjunction of the premises and that the premises entail the conclusion. Framing closure in this way avoids the threshold problem (since the conjunction must be known). If S knows the conjunction and believes q (as the result of competent deduction), then S’s belief that q cannot be false. This is the case because the truth of p entailing q, coupled with the truth of p itself, guarantees that q is true. This framing of closure, then, eliminates the considered counterexamples.

Framing closure in this way not only avoids the threshold problem, but plausibly avoids the defeat problem as well. Regarding undercutting defeat, it is at least much harder to see how S can know that p entails q while possessing such a defeater. Regarding rebutting defeat, it is implausible that S would retain knowledge of the conjunction if S possesses a rebutting defeater.

However, none of this is a real problem for Brown’s argument. It simply seems that she has ignored some possible lines of response open to the fallibilist that allows the fallibilist to keep some principle in the neighborhood of closure, which is an intuitive advantage.

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Brown, Jessica. Fallibilism: Evidence and Knowledge. Oxford: Oxford University Press, 2018.

Author Information: Steve Fuller, University of Warwick,

Fuller, Steve. “Counterfactuals in the White House:  A Glimpse into Our Post-Truth Times.” Social Epistemology Review and Reply Collective 6, no. 5 (2017): 1-3.

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May Day 2017 was filled with reporting and debating over a set of comments that US President Trump made while visiting Andrew Jackson’s mansion, the ‘Hermitage’, now a tourist attraction in Nashville, Tennessee. Trump said that had Jackson been deployed, he could have averted the US Civil War. Since Jackson had died about fifteen years before the war started, Trump was clearly making a counterfactual claim. However, it is an interesting claim—not least for its responses, which were fast and furious. They speak to the nature of our times.  Let me start with the academic response and then move to how I think about the matter. A helpful compendium of the responses is here.

Jim Grossman of the American Historical Association spoke for all by claiming that Trump ‘is starting from the wrong premise’. Presumably, Grossman means that the Civil War was inevitable because slavery is so bad that a war over it was inevitable. However well he meant this comment, it feeds into the anti-expert attitude of our post-truth era. Grossman seems to disallow Trump from imagining that preserving the American union was more important than the end of slavery—even though that was exactly how the issue was framed to most Americans 150 years ago. Scholarship is of course mainly about explaining why things happened the way they did. However, there is a temptation to conclude that it necessarily had to happen that way. Today’s post-truth culture attempts to curb this tendency. In any case, once the counterfactual door is open to other possible futures, historical expertise becomes more contestable, perhaps even democratised. The result may be that even when non-experts reach the same conclusion as the experts, it may be for importantly different reasons.

Who was Andrew Jackson?

Andrew Jackson is normally regarded as one of the greatest US presidents, whose face is regularly seen on the twenty-dollar banknote. He was the seventh president and the first one who was truly ‘self-made’ in the sense that he was not well educated, let alone oriented towards Europe in his tastes, as had been his six predecessors. It would not be unfair to say that he was the first President who saw a clear difference between being American and being European. In this respect, his self-understanding was rather like that of the heroes of Latin American independence. He was also given to an impulsive manner of public speech, not so different from the current occupant of the Oval Office.

Jackson volunteered at age thirteen to fight in the War of Independence from Britain, which was the first of many times when he was ready to fight for his emerging nation. Over the past fifty years much attention has been paid to his decimation of native American populations at various points in his career, both military and presidential, as well as his support for slavery. (Howard Zinn was largely responsible, at least at a popular level, for this recent shift in focus.) To make a long and complicated story short, Jackson was rather consistent in acting in ways that served to consolidate American national identity, even if that meant sacrificing the interests of various groups at various times—groups that arguably never recovered from the losses inflicted on them.

Perhaps Jackson’s most lasting positive legacy has been the current two-party—Democratic/Republican—political structure. Each party cuts across class lines and geographical regions. This achievement is now easy to underestimate—as the Democratic Party is now ruing. The US founding fathers were polarized about the direction that the fledgling nation should take, precisely along these divides. The struggles began in Washington’s first administration between his treasury minister Alexander Hamilton and his foreign minister Thomas Jefferson—and they persisted. Both Hamilton and Jefferson oriented themselves to Europe, Hamilton more in terms of what to imitate and Jefferson in terms of what to avoid. Jackson effectively performed a Gestalt switch, in which Europe was no longer the frame of reference for defining American domestic and foreign policy.

Enter Trump

Now enter Donald Trump, who says Jackson could have averted the Civil War, which by all counts was one of the bloodiest in US history, with an estimated two million lives in total lost. Jackson was clearly a unionist but also clearly a slaveholder. So one imagines that Jackson would have preserved the union by allowing slaveholding, perhaps in terms of some version of the ‘states rights’ or ‘popular sovereignty’ doctrine, which gives states discretion over how they deal with economic matters. It’s not unreasonable that Jackson could have pulled that off, especially because the economic arguments for allowing slavery were stronger back then than they are now normally remembered.

The Nobel Prize winning economic historian Robert Fogel explored this point quite thoroughly more than forty years ago in his controversial Time on the Cross. It is not a perfect work, and its academic criticism is quite instructive about how one might improve exploring a counterfactual world in which slavery would have persisted in the US until it was no longer economically viable. Unfortunately, the politically sensitive nature of the book’s content has discouraged any follow-up. When I first read Fogel, I concluded that over time the price of slaves would come to approximate that of free labour considered over a worker’s lifetime. In other words, a slave economy would evolve into a capitalist economy without violence in the interim. Slaveholders would simply respond to changing market conditions. So, the moral question is whether it would have made sense to extend slavery over a few years before it would end up merging with what the capitalist world took to be an acceptable way of being, namely, wage labour. Fogel added ballast to his argument by observing that slaves tend to live longer and healthier lives than freed Blacks.

Moreover, Fogel’s counterfactual was not fanciful. Some version of the states rights doctrine was the dominant sentiment in the US prior to the Civil War. However, there were many different versions of the doctrine which could not rally around a common spokesperson. This allowed the clear unitary voice for abolition emanating from the Christian dissenter community in the Northern states to exert enormous force, not least on the sympathetic and ambitious country lawyer, Abraham Lincoln, who became their somewhat unlikely champion. Thus, 1860 saw a Republican Party united around Lincoln fend off three Democrat opponents in the general election.

None of this is to deny that Lincoln was right in what he did. I would have acted similarly. Moreover, he probably did not anticipate just how bloody the Civil War would turn out to be—and the lasting scars it would leave on the American psyche. But the question on the table is not whether the Civil War was a fair price to pay to end slavery. Rather, the question is whether the Civil War could have been avoided—and, more to the point of Trump’s claim, whether Jackson would have been the man to do it. The answer is perhaps yes. The price would have been that slavery would have been extended for a certain period before it became economically unviable for the slaveholders.

It is worth observing that Fogel’s main target seemed to be Marxists who argued that slavery made no economic sense and that it persisted in the US only because of racist ideology.  Fogel’s response was that slaveholders probably were racist, but such a de facto racist economic regime would not have persisted as long as it did, had both sides not benefitted from the arrangement. In other words, the success of the anti-slavery campaign was largely about the triumph of aspirational ideas over actual economic conditions. If anything, its success testifies to the level of risk that abolitionists were willing to assume on behalf of American society for the emancipation of slaves. Alexis de Tocqueville was only the most famous of foreign US commentators to notice this at the time. Abolitionists were the proactionaries of their day with regard to risk. And this is how we should honour them now.