How do we differentiate pure lunacy from just a “different opinion” in philosophy?

Question

I’m having trouble understanding the point of philosophical discussion if each proponent of an argument can simply fall back on their intuitions such as what constitutes as evidence for their belief.

For example, a flat earth believer might think that any evidence that doesn’t involve a direct observation of a spherical earth from his eyes from outer space isn’t enough evidence. Or a theist might think that god is the most simple being possible vs. an atheist who may think it absurd to call an all powerful all knowing being anything but complex.

If these kinds of important questions come down to “opinion” and anyone can just fall back on their position by saying “eh, this just makes sense to me, you can’t prove me wrong”, how do we differentiate pure lunacy from “merely a different opinion”?

This kind of thinking seems to give equal weight to many different kinds of opinions which (intuitively) makes no sense and seems borderline dangerous, especially since there is presumably only one true reality. Rarely is there complete philosophical consensus on a matter. And even in the cases there is, it just begs the question of why we should care about that consensus.

Answer 1

Wittgenstein wrote in his Tractatus Logico-Philosophicus:

6.51 Skepticism is not irrefutable, but obviously nonsensical, when it tries to raise doubts where no questions can be asked. For doubt can only exist where a question exists, a question only where an answer exists, and an answer only where something can be said.

Swiftly followed by his last and most famous proposition:

7 Whereof one cannot speak, thereof one must be silent.

Sadly, no one took any notice...

Answer 2

Some questions may be unresolvable through more objective, robust and concrete methods, and they ultimately boil down to appeals to intuition. But I'm skeptical that this is really that often the case.

Rather, people are convinced by:

• More (in-depth) exposure to data

  99%+ of scientists accept evolution, and even more than that reject a flat Earth, for example.

  Even for questions commonly deemed outside the realm of science, scientists tend towards a particular view. For example, more scientists reject theism than in the general population.

• Understanding principles of logical reasoning

  This allows one to spot flaws in one's reasoning. Speaking from my own experience, in past times, I put far too much weight into reasoning that could've come straight from the fallacy section of a logic textbook. Only after exposure to the principles of logic, and to someone challenging my specific beliefs, did I spot those flaws.

  Paired with this, we might include an understanding of epistemology, the scientific method and statistics, as those are also used to get from some evidence to some conclusion.

• Significant self-reflection

  The things above might "forcibly" change one's beliefs, but they may not be necessary, and sometimes they may not be sufficient, to change beliefs.

  A big factor in changing one's beliefs is self-reflection: thinking deeply and very honestly about one's beliefs, consider which biases one might have, think specifically about whether you might be wrong, and emotionally accept that possibility. Having a strong emotional attachment to a belief often prevents one from thinking clearly. Reflection can reveal such beliefs, enabling one to question that, and allowing one to be extra critical in such places where emotion may cloud one's thinking.

  * Don't get me wrong: emotion isn't bad, it just doesn't belong on questions on truth, at least if one cares about what's true (which I'd argue you should).

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The above is first, and foremost, about oneself and about refining and questioning what you yourself believe.

It's easier to point those things at others, than to actually reflect on one's own beliefs. It's easier to dismiss someone who disagrees with you as needing to go "do their own research", rather than actually learning more about a topic. It's easier to dismiss someone as having some bias, rather than actually honestly considering where they're coming from and reflecting on one's own bias.

But just because it's easier doesn't mean it's intellectually honest or rationally justified.

Even people who have a true belief (as best I can tell) will still often dismiss those who disagree with them on that as being malicious or ignorant, rather than actually seeing where they're coming from. This doesn't make them wrong, but it is severely detrimental to changing the minds of those who believe what's false.

In any case, we can use similar means to the above to evaluate other people's beliefs (especially by asking them why they believe what they believe). In the process of getting to a well-supported belief, we may already have gone through the process of figuring out why opposing beliefs are unjustified. And if not, we could consider where someone is coming from and why they might believe what they believe. But as per the above, we should do so cautiously while giving others the benefit of the doubt.

Answer 3

Pragmatism? Like is your theory of any actual use? Sure you could believe there's a seven-headed dragon sitting on your shoulder, but does that help you answer any real world questions? Does it explain something? Is it measurable and quantifiable or at least allows for qualitative inference? Can you apply any of that anywhere so that you theory has any use to anyone at all?

Like the reason why both atheists and theists are able to stand on mutually incompatible positions is because none of them produces any actually useful answer to the question of whether (a) god exists or even what god is or isn't.

So yeah not being able to actually formulate a testable hypothesis makes them unfalsifiable, but it also makes them useless. So the actual problem is that there is nothing more than the intuition and the believe in the existence or inexistence of a god. There are no evidences, there are no applications of that or if there are they all are build on sand as the premise of the argument is just an assumption.

And resting your intuition on an assumption, while denying it's an assumption and assuming it's certain knowledge is likely pure lunacy, because you pick your premises outside of reality and basically defeat any attempt of other people to comprehend or make use of your claims.

While if you'd keep your awareness of the flimsiness of your axioms and just look as to where that would lead you, maybe to a testable hypothesis? Then you'd at least have something that other people can comprehend, they might still not agree with your premises or conclusions, but you can at least follow that chain of ideas and there might even be some merit to it.

So the point isn't to spout a theory and pretend your right discarding everyone that disagrees with you, but to learn something about reality and different opinions might provide a different perspective.

So idk the thing is the flat earth hypothesis actually worked fairly well for small scale civilizations. Like humans can see ~6km far, where you'd have a discrepancy of ~2m which is next to negligible. The radius of the earth is large enough that for a human any spot on it's surface appears to be relatively flat and that local topology is more important than earth's curvature.

The problem arise if you change your perspective and travel or try to understand celestial objects or both if you use celestial objects for traveling. Then your inconsistencies may go beyond what is negligible and into the realm of what is relevant for your measurements. So the change in perspective requires you to amend your theory to effects that you might have overlooked within the narrow focus of your own experience.

So having those discussions can nonetheless be fruitful, like even if you disagree with a conclusion you might still find value in the original problem that they tried to solve and that you might have missed or in the way in which people tried to solve a problem that doesn't work here but maybe somewhere else and so on.

Answer 4

We need to make a critical distinction between philosophical discussions proper and lay discussions on philosophical topics. Proper philosophical discussions fall into the realm of what Habermas called 'communicative rationality': a mode of discussion where the goal is to synthesize the strongest case for a given position. To synthesize the strongest case, we must necessarily engage and account for contrary evidence and argumentation. We can't just dismiss them with a hand-wave, or declare our disbelief, the same way we can't just wave away a rattlesnake in our living room. So long as we ignore or dismiss opposing argumentation and evidence, it will poison our own position. As someone (maybe Emerson?) once said (roughly), we want our opposition to be strong because it makes our victories more meaningful and our failures more useful.

Lay discussions on philosophical topics infrequently manage communicative rationality. They usually fall into one or more of Habermas' other rationality modes:

• Normative rationality: assert certain norms as unarguable true and argue from and in defense of those principles
• Dramaturgical rationality: take public regard as the primary metric of correctness and argue in ways that increase one's own reputation and decrease others'
• Teleological rationality: argue with the aim of achieving certain concrete goals without regard to abstract philosophical considerations

These modes of rationality — while not wrong in any meaningful sense — are not conducive to philosophical discussion. The first insists on certain points and will flatly deny any contradiction; the second is concerned with impression management and will avoid or subvert anything that looks problematic; the third is overtly manipulative and unconcerned with higher principles. And while each of these can be coped with by itself, the fluid nature of lay discussions can run through all of these modes, with one participant switching modes midstream or different participants injecting different modes. That becomes unmanageable because the implicit rules of discourse are constantly changing.

The point is that if you want to do philosophy, find people willing and able to engage in communicative discourse. And if you wan to do politics, be aware of what the people you're engaged with are doing, and adapt as needed. It isn't a fruitless exercise, just a difficult one.

Answer 5

You're hitting on one of the most entangled knots in philosophy. Some classic adumbrating examples:

• The hard problem of consciousness is hard
• Solipsism cannot — and will not — be rebutted
• There's no a priori choice between materialism and idealism
• Or rationalism and empiricism
• All the myriad 'obvious' truths of science rest on metaphysical — ie. non-scientific — assumptions
• Falsifiability is neither falsifiable nor verifiable
• In logic there's Aristotle. There's Nagarjuna
• Atheists and theists have been breaking each others' heads for millenia
• Plato is the fount from which all western philosophy follows as 'footnotes'. And today in philosophy circles, to be a Platonist is a euphemism for being a nut
• And the posts closed/deleted on this site are the unworthy opinions in the opinions of the most opinionated.

Answer 6

I don't think this can be solved purely objectively. In practice, the solution usually comes down to concensus.

For instance, if there are 10 people in a room, and only one of them hears a voice, we consider them to be an outlier who may be suffering from a mental disorder. He personally may think the voice is real, and everyone else has a hearing problem or there's a conspiracy trying to gaslight him. But the 9 vs. 1 majority is usually assumed to be correct.

Of course, concensus isn't always right. There was a time when most people, including those who would be considered "experts", believed the Earth was the center of the universe. They just didn't have enough information to come to the correct conclusions. Even though concensus may not be right, it's still the best approximation we have at any particular time.

People who go against concensus are often treated as delusional. But if they're right, others should eventually come around as evidence accumulates. That's how heliocentrism eventually won over the geocentrists.

A solipsist might say that only what they perceive is real, so the opinions of the concensus are irrelevant. But in that case, the original question becomes moot. There's nothing to differentiate, the solipsism assumption already gives the answer.

Answer 7

All questions, ultimately come down to "opinion".

There are several ways to demonstrate this.

• Empirically, all our observations are direct and first person -- IE judgement based on our own interpretation of our sensory inputs. Science is generally done using intersubjective consensus.
• Rationally, our reasoning is done using a specific logic system, and is based on assumed "premises". Assumptions are -- intuitively chosen. And there are an infinity of logic systems one could use to try to reason. Mostly we use classical logic, but that is a judgement call as well.
• The Munchausen Trilemma demonstrates that all our justifications must ultimately trace back to unjustified assumptions, to logical circularity, or to an infinite series that we can never complete.

Your objection is that opinions are unevaluable, hence any knowledge traced to them is -- useless.

This is incorrect.

We have developed a variety of methodologies that are highly useful in solving these sorts of judgement questions. Here are examples:

• Science pursues the "infinite series" leg of the Munchausen Trilemma. Ask why, then get an answer. Then ask "well, why does THAT answer hold true", which generates another investigation. Science has generated a deep branching tree of answers, which all eventually trickle out to "we don't know why THAT is the case yet", but by providing partial answers and justifications, it provides a highly useful although incomplete set of working conclusions.
• We are each highly subject to confirmation bias. We want to believe what we find intuitively satisfying, and are hardwired to look for confirmations rather than refutations of our views. It is people who disagree with us who are generally able to most clearly see holes and flaws in our views. Dialog with those who disagree is essential to actually finding out the errors in one's own thinking.
• Scientists are also subject to confirmation bias. Science therefore needs to look for falsifications, rather than confirmations. Popper's falsifications was a good first approximation to how to do science but it was "falsified". The best method to do science is Lakatos' Research Programme methodology: https://www.scientowiki.com/Imre_Lakatos
• What Lakatos's approach calls for is a recognition that there are MULTIPLE credible ways to approach most problems, and pluralism and competition between these views is what one should expect and celebrate in pretty much any field.

How to apply this to settling differences of opinion?

IF you have a community of people committed to accepting:

• there are other possibly valid ways to thinking about a subject (accept pluralism -- there are competing Research Programmes),

• AND taking possibly faults with their own way to thinking seriously (Programmes must acknowledge problems even if put on a back burner),

• AND committed to intellectual honesty rather than reflexive defense of their view,

• THEN they are generally able to reach a consensus on the validity of evidences, reasoning methods, and the consequences of both.

Your objection to mere opinions, or even consensus of opinions is, I suspect, because so many people do not satisfy the first three bullets of the above list, so their consensus is not likely to be actually true.

Answer 8

Question: "How do we differentiate pure lunacy from just a “different opinion” in philosophy?"

Short Answer: By analyzing the subject's use (or non-use) of logic and determining whether or not they have a conscious disregard for logical reasoning.

Explanation: I agree with the only contributors who have brought up the principle of logical reasoning. I think what first has to be done in answering this question is to define lunacy. In this context, the best dictionary definition for lunatic is likely "an extremely foolish or eccentric person." The definition of foolish can be "(of a person or action) lacking good sense or judgment; unwise."

I would argue that someone is unwise or lacks good sense or judgment as someone who disregards logical reasoning when stating their propositions and beliefs, especially as those beliefs move on the spectrum towards being a deeply held conviction.

If someone has not studied logical reasoning, and knows not how to apply it, then I wouldn't say they are foolish (or a lunatic) nor do they have a "differing opinion," but rather they are misguided or unguided. Ideally someone with a differing opinion is one who can present an idea logically and have a differing stance of the truth value of a premise, and form some basis for this. Sometimes this can be in whether or not to believe in an implied or assumed premise.

If someone has studied logical reasoning, or is presented with logical counterarguments pointing out the logical contradictions in their held beliefs, then I would say they "lack good sense or judgment" and are "lunatics." A conscious disregard for logical reasoning, in my opinion, is synonymous with disregarding the rules to which everyone is subject to and must play by. A basketball coach could be justified in calling an opposing player a lunatic if said player enters a basketball game, disregards the rules and referees, and simply runs out of the building with the basketball while thinking justifying his position that he is playing basketball. At this point he is not playing basketball while claiming to play basketball; lunacy.

I do want to note that lunacy and lunatic are strong words which often cause a listener to be offended. if lunacy is equated to something with less connotations like simply "the conscious disregard for logic" then the answer is much easier.

Answer 9

As a lay philosopher you have fallen into the trap of mistaking mere opinion with the exquisitely reasoned judgement of the professional. When I pronounce my views on the interdemarcation of parasymotic destratification, I am not making the kind of vacuous subjective claim that you might when asserting that McDonald's is better than Burger King. As for there being only 'one reality', that is exactly the sort of simplistic nonsense that the professional would expect the lay philosopher to spout. In any case, the true philosopher does not allow herself to be fettered by something as trivial as reality. Consider McTaggart on time, and the countless pages written in response, none of which would have happened had as pedestrian a description of reality as General Relativity been allowed to stand in the way. And of course, yes, philosophers are passionately concerned about consensus, since were it ever to be reached it would mean an end to their fun and games.