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Rational Disagreement and Normative Impossibility
Matjaž Potrč, University of Ljubljana
Rational disagreement tends to be approached by credences, involving quantitative probabilistic notion of partial belief, with the aim of conciliation. Strength of belief as qualitative notion is proposed, with nonconciliation as the result of dialectics that typically goes from belief being weakened to its becoming stronger. The insight which upholds belief disagreement relies upon lots of evidential information that chromatically illuminates the judgmental scene without being explicitly present in consciousness. Evidential support for a belief is one’s best take upon its objective justification, as the proper rational disciplining of the symmetry challenge. Each of peers in dispute needs to rely upon her/his sensibility that relates her/him to the underlying epistemic normativity. Evidential normatively supported sensibility is also the appropriate take on normative impossibility.

Keywords: rational disagreement, global and local peerhood, dialectics of disagreement, evidential belief justification, Potrč’s principle, normative impossibility.

0. The plan
Rational disagreement has to do with beliefs, so the approach to belief in quantitative credence and in qualitative strength manners are considered. Phenomenology of rational disagreement distinguishes between global peerhood and between local peerhood. The strategies to approach the phenomenon of rational disagreement aim at conciliation and again at nonconciliation. The first one takes rationality’s job to be avoidance of malign contradiction, whereas the second one buys benign incoherence accommodated rationality. Symmetry challenge comes from the conciliation strategy, whereas the reply to it relies upon nonconciliation. This last one builds upon ethics of belief. It is tentatively suggested that Potrč’s principle may be a guidance towards approaching normative impossibility.

A. How to approach beliefs in rational disagreement?
The shape of rational disagreement phenomenon will get clearer as we proceed. For starters though we may present it as a situation which involves two agents who defend opposed views. As people engage in such a situation, we may say, they uphold adverse beliefs. I cling to the belief that p, whereas you believe that -p is the right choice. We thus have to do with a tension between beliefs that each of us separately upholds. The disagreement is thus in our beliefs. But just what is the rational procedure to deal with these disagreements? The way to look at this question depends upon the manner in which beliefs and their justification basis get construed.
	One usual way to approach beliefs in the rational disagreement cases is by -- as these are called -- credences, which present a quantitative, probabilistic take upon beliefs. Credences are meant to be grades of belief or even partial beliefs. There are two versions of this approach. The soft credence approach takes all graded beliefs to be a kind of everyday beliefs. The question about the rational approach to beliefs that should be pursued in this case has to make a choice between conciliation and between nonconciliation strategies, about which we will say more from the next section on. The question about what degree of epistemic confidence should be assigned to a belief under scrutiny is then just a secondary problem to be subsequently solved by this soft approach to beliefs as credences. The hard credence approach does not take most of ordinary beliefs to be beliefs at all, for it imposes a condition for beliefs by the degree of epistemic confidence 1 only, and this one is accorded by it just to beliefs figuring a priori claims and necessary truths. We do not think that credences, i.e. degrees of belief, offer an appropriate account of beliefs. Between two approaches to beliefs as credences though, we engage into discussion with the one adopting soft credences, for it at least stays close to the everyday phenomenon of belief, which cannot be claimed for credences construed in the hard manner. There is something right with this last approach nevertheless, although in a distorted way. The hard credences approach namely takes beliefs to be 1 on the degree of confidence scale, just that it does not think this place to be occupied by any ordinary beliefs at all, and rather just by a priori and necessary truths. And degrees of confidence in belief justification are basically just wrong as rendering an appropriate account of beliefs. They invite the introduction partial beliefs, which fail to be attuned to psychologically reality.
	Just what may be opposed to partial beliefs? One can see that the concept of partial belief underlying credence guided accounts is quantitative. One tries to assign the degree of confidence, or the degree of justification for a belief, which then results in partial beliefs entering the stage. In opposition to this we think that beliefs are qualitative. Beliefs are upheld full stop or they aren’t upheld at all. In this respect hard credence approach is correct, as we have indicated, just that it dismissed ordinary beliefs from the scene. So in overall it is even wronger than soft credence approach that stays with graded or partial ordinary beliefs. Partial beliefs just cannot be there. One should first subscribe to full beliefs, i.e. beliefs that are there at the point 1 on the confidence gradation scale. If point 1 epistemic gradation is the only appropriate one for beliefs, then partial beliefs of soft credence cannot pass the point of scrutiny. Point 0, zero point on the degree of confidence scale is the refusal to form the belief in question. So zero point may be the belief that -p, in opposition to the degree 1 point which is there for the belief that p. Once as we agree that beliefs cannot be partial, and that they can be just full beliefs, the question of these beliefs’ quality comes into the foreground. This one may be introduced through the strength of belief, which is a qualitative notion. The fact that beliefs have strength is not mysterious at all, and it is rather an ubiquitous phenomenon. Take the example of two statements where beliefs in their support are comparably well warranted for most of us: Rome is the capital of Italy and Aristotle was the teacher of Alexander the Great. We do believe these statements, and there are various other statements that we do not believe at all. As both of the mentioned statements go, our evidential support suffices for propositional justification of beliefs that are related to them. However there is more of evidential justificatory support for the belief that we have in the first case, as compared to the evidential support for the belief that we possess for the second case. We can say that the strength of belief is bigger for the first case, in comparison to the strength of belief that is weaker for the second case. Strength of belief obviously depends upon the evidential support that is available for that belief to the one who forms it. We seem to have stronger evidential direct salient justification support for the mentioned Rome related belief in opposition to the Aristotle related belief where our available evidence is rather remote and mediated. The strength of belief by someone in Aristotle’s vicinity may have been just opposed to our situation.
Once as one adopts the notion of belief’s strength, beliefs will be just full beliefs: one upholds a certain belief, or one doesn’t. Qualitative variability then comes with belief strength. If beliefs are just 1 or 0 cases upon the probability scale, it turns out that degrees of probability and credences are not really applicable to them. Partial beliefs turn out to be a psychological myth. In simple terms again, you believe something or you do not believe it. But there may still be the strength of a certain belief involved. Strength of belief is related to its justificatory evidential support. It is expressible in comparative terms, such as I strongly believe that p, or I somehow weakly, barely believe that p. 
The quantitative construal of beliefs as credences and admission of the existence of partial beliefs is opposed to the qualitative construal of beliefs possessing their strength. The way to look at the evidential support for both of these cases will be different. In fact, it seems that quantitative way to go will not need to rely upon evidence in other than objective mediated manners, whereas qualitative strength of belief approach will need evidence in a more directly engaging manner, where the one who believes is subjectively involved. This will be shown in the choice of rational procedures that go along with each of these cases. Credence take upon beliefs goes with conciliation as the rational strategy to be embraced in rational disagreement cases. Strength of belief approach though goes with the strategy of nonconciliation as a rational way to go in the case as one faces rational disagreement. 

B. Phenomenology of rational disagreement
In order to tackle the rational disagreement cases we begin by phenomenology that is involved into them, characteristic for the situation. The following presentation thus succeeds by conveying phenomenology that is involved into the phenomenon of rational disagreement. The phenomenological or what-it’s-like experiential assessment of rational disagreement targets qualitative feel for someone who finds herself/himself in that situation.
	We begin by distinguishing two varieties of peerhood: global peerhood and local peerhood. In the case where I treat the person with whom I am engaged into rational disagreement as my global peer, I grant him that he shares with me the expertise in the wide area where we try to make our opinions value. I observe my global peer with all respect in relation to the wide area, and can even think about him as my global superior. The person who is my global peer also treats me as his global peer, ascribing to me the expertise in the widely construed area where our discussion takes part. So, as related to the wide area of our concern, we treat each other respectfully as global peers. Local peerhood supports a different phenomenological what-it’s-like experience. Yes, we treat each other as global peers, and nevertheless there may be disagreement between us, in respect to some specific question in the wide area. It may be that the person whom I treat as my global peer or even as my global superior in the wide area under scrutiny is treated by me as my local inferior. This is how I qualitatively experience the situation.
	Rational disagreement may be seen as a case aiming towards conciliation, and again as aiming towards nonconciliation. Examples of rational disagreement will be given at this stage. Notice that decision for one or another way to treat rational disagreement depends upon the construal of belief that we have presented in the former section. If the belief is understood as credence, i.e. as quantitative epistemic take upon its confidence, then the situation of rational disagreement will be handled by the technique of conciliation. The name of this procedure indicates that some kind of adjustment or middle ground will be searched for, so that the disagreement tension will be thereby reconciled. If on the other hand beliefs are understood as qualitative, variable strength involving all or nothing embracing points upon the gradation scale, then the proposed procedure will be likely that of nonconciliation. This expression indicates that there will be no graded adjustment searched for, as it goes for the quantitative case, but that each belief will try to persist in its own quality, although its strength may be varied along the rational disagreement process. In fact, nonconciliation typically aims to strengthen each participants’ belief in respect to its own unique quality. The strength and the quality of each belief will be thereby supported. The quality of individual beliefs will not be important though if these are treated as credences. 
	First consider a case of conciliation (Christensen 2009), with phenomenology that is involved into it. You and myself have lunch together in a restaurant. Before the bill arrives we decide to calculate the amount that we are due. My result is 42 €, and your result is 46€. We both trust one another in respect to the basic mathematical skills, and we did not have too much to drink. I treat you as my global peer, and you treat me as your global peer, in respect to each other’s calculating skills. I also treat you as a local peer, even if our resulting beliefs diverge. Given that our results contradict each other though, what is the natural way for us to do in such a situation? The rational thing to do, so it seems, is to suspend our beliefs. Each one of us thus abandons his belief. We then go back to the drawing board in order to calculate the correct amount that we owe the restaurant. This is a case of conciliation. Notice that we did not jump towards the conclusion of the average value which would be 44€. Showing respect of global peerhood and of local peerhood for each other, we suspended our beliefs, and we made the effort to get to the result that would be objectively supported by both of us. We will come at the common, objective belief through abandoning our beliefs that we produced at the first stage of the disagreement process. We end up in conciliation.
Here comes a case of nonconciliation. We are philosophers. We treat each other as global peers, i.e. in the area of our study we have respect for each other. We know each other’s argumentative moves. I may even treat you as my epistemic superior. But in respect to some specific question I may disagree with you. I may be compatibilist in respect to free will, and you may be a libertarian. In respect to local peerhood thus, there will be disagreement between us. This disagreement will only accrue as we engage into discussion, although its strength may diminish at the first stage of our engagement, as I hear your worrying questions about my position, and as I try to present hurdles that are there for your view. In respect to local peerhood, I will observe you as my local inferior. And you may do the same concerning my position.
Here comes a further nonconciliation case. I may treat David Lewis as my global epistemic peer. And I certainly treat him as my global epistemic superior. But in respect to his belief into the genuine existence of possible worlds, so that the actual world is just an indexical choice on the basis of that metaphysical multitude, I treat him to uphold a rather skewed belief. Most of philosophers who spent some time with this issue happen to have a similar opinion. Though he was a philosophical genius, I treat David Lewis as having misguided belief in respect to this particular question. Both of just reported cases are the ones of nonconciliation, for I treat my global epistemic peer or even superior as my local epistemic inferior, and I may expect similar reaction from his side in respect to myself. Notice that my dismissive opinion is just in respect to the specific question under scrutiny, and thus its target is not some overall and not well profiled attitude. What happens in the case as the nonconciliatory strategy in respect to rational disagreement is that the opposed beliefs remain in their strength and even accrue their strength after the initial phase in which they may lose some of it. 
Notice that phenomenology of rational disagreement shows how conciliation strategy tries to attain some middle quantitative ground between the participants’ beliefs, all in preserving global and local peerhood attitudes. But this succeeds with the cost of suspending one’s belief. Nonconciliation strategy retains global mutual peerhood attitudes and respect, without also adopting local peerhood feelings. This enables each of beliefs to be retained, and to typically increase in their quality.

C. Rationality of rational disagreement
Here is a further hint about the differences upon the basis of quantitative take upon beliefs as credences and their conciliatory strategy on the one hand, and between the qualitative take on beliefs as full-fledged entities that come with a certain strength in the situation, together with their proposed nonconciliatory strategy. Which of these opposed tactics in treating the phenomenon of rational disagreement is rational?
One main idea is that conciliatory strategy is hard, whereas nonconciliatory strategy is soft, in the following sense. Behind the hard line strategy, there seem to be the following presuppositions: (Ha) Opposed views of the participants involved into rational disagreement amount to a malign kind of contradiction, for one of them supports belief that p, whereas the other party subscribes to the belief that -p. (Hb) This objectively existing malign kind of contradiction may only be rationally resolved by the involved parties abandoning their beliefs, so that they may come to a common ground which will leave both their global and local peerhood feelings intact. The hard strategy is an objectivist take promoting conciliatory political correctness. Behind the soft line strategy, the following presuppositions seem to be effective: (Sa) Rational disagreement just displays a benign kind of incoherence that is viable and may be spotted in different areas of human engagement. (Sb) The benign kind of incoherence has a tendency, if taken with the needed deontic sensibility, to accrue the strength of each individual belief, thereby improving its quality. Diversity of beliefs and their coexistence strengthens each person’s subjective belief quality and evidential justificatory force. Soft strategy thus promotes nonconciliatory political correctness. One sees that conciliatory rationality is exclusivist, for it tries to exclude what it perceives as hard malign contradiction that is involved into the phenomenon of rational disagreement. The nonconciliation strategy to the contrary is inclusivist, in the sense that it allows for the persistence of opposed beliefs that it just treats as benign incoherent quality promoting matters -- and the real quality, according to this view would not be there if there would not be dialectic engagement in the situation of rational disagreement.  
The main question is how to react to the disagreement in a rational manner. What does rationality require? We have indicated the difference between hard and between soft line tactics in approaching rational disagreement tensions. There are also two targets of one’s attention which go along with these tactics: the upshot of the process, or the dialectics according to which typical cases of rational disagreement happen. People sticking to beliefs as quantitative credences and subscribing to conciliation tend to concentrate at the upshot of the disagreement process. Another and somehow underappreciated way to go is paying attention to the dialectics of the process through which the rational disagreement unfolds. Conciliationists think that rationality requires one to suspend one’s belief, to adjust it, without sticking to one’s guns. They are right, as we would say, in the respect that one’s belief, as one enters the situation of disagreement, first diminishes in its strength. Thus far this would support conciliation. But in rational disagreement disputes, where one treats one’s epistemic peer as an equal or even as one’s superior, the strength of one’s original belief tends to increase after first getting diminished, as one considers the opponent’s opposed thesis and tries to counter his criticism, thereby reconsidering and rebuilding the evidential basis of one’s opinion. One may stick to one’s belief, even after all the contrary theses are given. And one may treat his global epistemic peer as one’s local epistemic inferior, lacking the insight that one has oneself, and so being skewed in respect to a specific issue. The dialectics of rational disagreement finally supports nonconciliation. The strength of belief may diminish as one hears opponent’s opinion, but then it typically increases if one did not suspend one’s belief and now may profit from the opportunity to support it by construing arguments that deflect stated objections. The evidential base of belief gets stronger.

D. Symmetry challenge
Here is symmetry challenge for the rational disagreement. It targets the question of rationality, for the case of nonconciliation, i.e. for the case where each of the involved parties retain their opposed beliefs. It may be presumed that the challenge is spelled out from the point of view of conciliation and quantitative beliefs strategy. It is indicative that there is no such challenge targeting conciliatory position.
	In the case of rational disagreement where you take nonconciliatory tactics on board -- the challenge goes -- you observe your opposed party as your global peer, possessing due expertise in a broadly conceived area under question, and showing respect to him, perhaps even treating him as your global superior. You also take him to be your local inferior, i.e. to be skewed in his views concerning a specific question under scrutiny. This allows you to increase strength and thereby quality of your own belief. Suppose that you are right in this, and that the support that you have for your belief is warranted. But now, the symmetry issue comes into the foreground. For your opposed party follows the same tactics as you do. He treats you as his global peer, but also as his local inferior, which allows him to support his own beliefs. The question now arises why under heaven should one adopt your views, in disadvantage to your buddy’s views, or why one should go the other way round. Given that there is symmetry in the tactics that you follow, there does not seem to be any reason around for privileging one’s belief at the cost of the other’s beliefs. There is no rationality around that would advise you to take such a step.

E. Replying to symmetry challenge
Symmetry challenge seems to be well taken. Rationality really does not appear to authorize exercising any favor in one or other direction featuring a symmetry situation. But notice that the symmetry challenge is spelled out from the position of credences and conciliation tactics, following hard take on the involved rationality, and presenting the dispute between epistemic peers as the one involving malign contradiction. As against this one may take soft line and look at dispute as featuring a benign form of inconsistency that should not be avoided at all costs but rather happily embraced, as it underlies many quality providing results in our everyday life. The point of view of nonconciliation and qualitative beliefs strategy will need to spell out a different sort of rationality as is the one that underlies symmetry challenge and subscribes to the hard contradiction involving approach that is present in the conciliatory tactics. 
How should this alternative rationality that is in support of strength of belief and nonconciliation be spelled out? We can start answering this question by considering the position of Peter van Inwagen (1996) that we are sympathetic with, as it defends nonconciliatory tactics. Talking about David Lewis with whom he disagrees, van Inwagen first confirms global epistemic peerhood: he takes Lewis to be an excellent philosopher and an expert. Both of them, one may presume, are rational, knowing all of each other’s argumentative moves, which they have played through several times. And yet, in respect to a certain specific question, as is the one concerning free will, Lewis’ opinion seems to be just wrong to van Inwagen, and Lewis beliefs in respect to the specific question under consideration appear to him to be skewed. But just what can authorize him to hold his view in face of such excellent challenger? In respect to this, says van Inwagen, I just have some insight that my peer does not have. Given that van Inwagen’s position is that of nonconciliation, we may ask about rationality that supports the mentioned insight, and that would thus be a viable match to conciliation embracing hard contradiction view concerning the tension that is there in rational disagreement situation.
The soft rationality in question will have to do with a view concerning beliefs that would support treating rational disagreement situation as providing a kind of viable benign incoherence that is directed towards quality. The question will be about the evidential support of belief. Notice that conciliation tactics sees belief to be evidentially supported by quantitative gradation, leading it to adopt partial beliefs. The evidential probabilistic support will use just explicit features. The nonconciliation, on the other hand, uses what may be called implicit features as underlying the evidential support for beliefs.
Two implicit forms of evidential support that a nonconciliationist may embrace come from psychological data and from the rationality of belief formation considered in philosophy of science. The psychological part of evidential belief support will be illustrated through chromatic illumination and morphological content. The philosophy of science stuff in respect to the evidential belief formation will be sketched by the help of the frame problem and through a look about the actual evidential support of beliefs in that area.
The way beliefs are formed and evidentially supported in respect to their psychological effectivity may be illustrated by the example of joke-getting. Much of the information that is there as one gets a joke comesin an instant, without that it would be explicitly given. Yet the one who gets the joke has to appreciate all this information, for without that he would not be able to get the joke. One may say that the evidential information that supports the joke-getting is in the cognitive background, and that it chromatically illuminates the situation. The evidence has an effect upon the perceived scene and point, without that it would appear upon the scene in an explicit manner. The idea of chromatic illumination may be delivered by the example of the painting, where the illumination of the scene has an effect upon its perceived quality, yet in such a manner that the light sources are present outside of the scene itself. This shows that the psychology underlying insight and sensibility relating one to normative evidential support does not all need to be explicitly there, and yet that it is qualitatively efficient exactly through this background working.
In a similar manner, there is an implicit support of belief formation in science. Trials in cognitive science to model the upgrade of belief system at the time as it receives new information -- presumably an ongoing process -- encounter frame problem, namely the problem how to determine the exact amount of information needed to make such an upgrade effective. Just which information should be retrieved from the memory bank in order to determine what would be a rational course to take in the given situation? If it rains, the information would involve taking umbrella. But how can the system ascertain this without before that retrieving all the rest that it knows -- which would make the procedure ineffective. But we humans are solving such problems all the time on everyday basis. It has been noted that belief upgrade in science encounters holistic features of isotropy and Quineanism, the first one telling that each information a scientist knows may be important for all else that he comes to believe, and the second making holistic impact even stronger. (Fodor 1983, 2001) The evidential justificatory support for a belief thus comes in an indirect manner, and not explicitly. 
How can these facts about belief formation and its justificatory evidential support help to provide a reply to symmetry challenge posed to a nonconciliation approach concerning rational disagreement? The question was about what authorizes my view as against my opponents view. A hint was that one may invoke an insight that one has. This insight will only be authorized though if it will be properly evidentially supported, i.e. if the belief that it offers will be justified in this manner. Evoking data from psychology and from belief formation in science will provide some support, showing that implicit information is important in this, our challenger will say now, but the symmetry challenge still persists.
This question has to be answered by what may be called ethics of belief. The answer to the challenge is that in cases of rational disagreement the quality of belief should come first, without that the opposed beliefs should necessarily be viewed as contradiction. At least this goes for such cases as the ones involving diversity of opinions.

F. Ethics of belief
Before going on, some more things in respect to the earlier mentioned insight supporting nonconciliatory view should be specified. If I have an insight, then there is a sensibility in accordance to which I operate. This sensibility relates to the normative basis of what is at issue. In respect to beliefs, one may talk about epistemic sensibility. Just what makes my beliefs justified? The answer to this question may go through evidential support for the belief in question. Insight for correctness that one experiences for one’s belief comes through sensibility by which the evidential justificatory basis for that belief is approached. What is the rationality that fits this basis? Our look at how the evidential basis for a belief functions in respect to its psychological characteristics and then in respect to the way beliefs are formed according to testimony related to scientific theories provided an entrance into the realm of what we may call soft rationality, i.e. the rationality that allows for benign incoherence at the expense of the exclusivist malign contradiction hard point of view.
Here is the summary of the discussion in previous section. Not all of the evidence that makes a certain belief justified is explicitly presented by the one who upholds that belief. Much of evidential justificatory support for a belief happens outside of one’s explicit attention. Nevertheless, evidential support is still there, being available through chromatic illumination. Beliefs are features belonging to the higher cognition, involving such matters as intentional content, thought and reasoning processes. Higher cognition is holistic and it cannot be modelled by tractable exceptionless representational rules, in opposition to modular reflexive processes, where cognitive science could make empirical progress. In epistemic matters, much of a certain belief’s support comes from the cognitive background that is provided by the morphological content (Horgan-Tienson 1996). This is the content that is “in the weights” of dynamical cognitive system, such as it may be approached by connectionist models. The evidential support via chromatic illumination for a belief (Horgan-Potrč 2010), comes from the cognitive background. The two topics concerning humans’ cognitive abilities and their evidential normative justificatory support are thereby connected. Both strength or quality of a belief, and its normative justificatory evidential support via chromatic illumination are important for the way in which we approach the topics of rational disagreement.
	Now, against the symmetry challenge, one may say that, despite that the opponents in dispute made explicit all of their argumentative moves, the fact that their disagreement in belief as to p or again as into -p still persists has to be due to some implicit evidential support that is effective in belief formation. This may be in support of the nonconciliatorily support for the ethics of belief. The ethics of belief, one may say, supports the need for one to stick to one’s beliefs, and not fortuitously abandoning them or quantitatively adjusting them in disagreement situations.
	What are the possible guidelines to support belief that would offer a reply to the symmetry challenge? One may start with the principle Van Inwagen gives upon the basis of the view defended by Clifford in the paper “The Ethics of Belief” (1877):
Clifford's Principle: It is wrong always, everywhere, and for anyone to believe anything on insufficient evidence.
Van Inwagen also sets for another principle that he thinks is defended, in effect, by Clifford, which van Inwagen dubs “Clifford's Other Principle”:
Clifford's Other Principle: It is wrong always, everywhere, for anyone to ignore evidence that is relevant to his beliefs, or to dismiss relevant evidence in a facile way.
We believe that both of these principles are best followed by:
Potrč's Principle: It is wrong always, everywhere, and for anyone to form beliefs, or fail to, in ways that go contrary to her/his experiential best take on the net import of the available evidence.
Potrč's Principle goes with evidential seemings that support the insight which is there for the participant in the rational disagreement. The idea is that, if one is attentive at what constitutes evidential justification for someone involved into rational disagreement, there is really nothing else around as that participant’s experiential best take. The fact that this one is constitutive in sensitivity leading one to normative evidential justificatory support for one’s belief dismisses the worries posed by symmetry challenge. There is just first person point of view justification for evidential support of beliefs. There is no objective third person point of view justification possible in such settings. Sticking to one’s best evidential take as the support for one’s beliefs relies upon good faith in forming one’s beliefs. This is the ethics of belief angle. There is no other better experiential evidential support for one’s beliefs than is the careful consideration of one’s justificatory support, which comes in partially non-explicit, chromatic illumination manner. Potrč’s principle encompasses both formerly mentioned principles. And it embraces nonconciliation.

G. Rational disagreement and normative impossibility
Normative impossibility is an impossibility that is adjectively specified, namely in respect to normativity. If a norm prescribes that you should not lie, then it is normatively impossible for you to lie, i.e. if you wish to stay in accordance with the norm, it will not be possible for you to lie. This does not exclude metaphysical possibility: it may still be an empirical fact that you have lied, but it was not possible for you to act in accordance with the mentioned norm as you did that.
We have taken nonconciliatory position in respect to rational disagreement. This position advises you to follow your own insight, your best evidential take on justification of your beliefs, which will typically not be all explicitly present. You should follow your sensibility, and this sensibility of yours connects you to the epistemic normativity. Potrč’s principle obliges you to follow your experiential best take on the net import of the available evidence. This accords with ethics of belief, for there is no other, objective third person perspective that would make your beliefs justified. The objectivity of belief’s justification you can just get via your best good faith careful engagement in the matters that support your belief. If you would abandon the belief that you have, under this circumstances, this would amount to your exercising matters in bad faith. But this seems to be wrong in respect to your epistemic justificatory engagements. Ethics of belief and Potrč's Principle give another dimension to normative impossibility. If you follow your epistemic seemings, your experiential best take on the net import of the available evidence, then it is just normatively impossible for you to form beliefs in any other manner.

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