What is it to know what a thing is? Suppose I can identify a laurel tree by its smell, but not by the shape and colour of its leaves. Or the other way around. Do I know what a laurel tree is in each of these cases? Or suppose I am a scientist and can identify it by analysing its genome, but not by its smell nor by the shape and colour of the leaves... Suppose I know only or, on the contrary, do not know the uses people give to laurel leaves. How many properties of laurel must I know so that I can know what laurel is? I think I must know something, otherwise I wouldn't even know what the word"laurel" means. But what? It can't be just one small thing: I wouldn't say that I know what laurel is if I can identify it only by its smell.

Great question(s). I suggest that "the bottom line" philosophically in such matters involves whether your concept of a "laurel" enables you to identify the plant as distinct from other plants and things in general (including minerals, animals, computers,...). Another criterion that philosophers use involves identifying what features are necessary or sufficient for a thing to be what it is. Such an analysis will probably take shape in terms of differentiating a thing's essential characteristics from its accidental features. So, I assume that an essential feature of being laurel would be being a plant, but it would only be an accidental feature that the plant was used in ceremonies to make a kind of crown that was conferred on someone quite distinguished (a successful poet, say). Because things like laurels will have almost indefinitely many features (the way it tastes, the sound it makes or does not make, when harvested.....), we tend to prioritize what features are vital depending on the context. So, for...

Through some years of philosophical study I've become confused about what exactly it means for me to have knowledge. What was once a familiar and seemingly clear concept has now become unfamiliar and obscure. Can it be made clear again for me? Can I ever know whether or not I know? It seems as though the more I read about knowledge the more obscured it becomes.

The topic of knowledge is an old one, going back at least to Plato who wrestled with the difference between knowledge and correct opinion. The traditional, most common understanding of knowledge is that a person knows X (whatever X stands for) if that person has a true, justified belief about X. Justification refers to evidence. This traditional understanding of knowledge has been challenged on the grounds that you might have a justified true belief about X --that Pat Jones is in Spain-- and yet the justification / evidence is spurious, e.g. imagine you are seeing Jones' identical twin, Chris Jones, in Spain and you inappropriately conclude you are actually seeing Pat. This has caused some philosophers to amend the definition to: A person knows X if the person's belief is true and the evidence for this belief does not involve essential reasoning by way of a false premise. Matters that remain unsettled include (a) Just how much evidence or justification is needed for one's belief to count as knowledge,...

I want ask about our trust to others, how we can thoroughly trust to others? How we know that we trust to right people? Why we must trust to others and what impact if we hard to give a trust to others?

The topic of trust is very, very important on all sorts of levels, from everyday exchanges, to contributing to this website, to ordering food at a restaurant, signing a loan to buy a car....In fact, it may be that TRUST of some kind, even if it is the minimal sense of having to trust your own thinking, may play an important role in virtually all our waking hours. I will put to one side whether there is trust in dreams! First consider a few observations about what is trust... At least in English, the word trust may be used widely; I might trust my computer to work, trust that it will not rain when I have to work with the homeless this afternoon as part of a charity project, and so on, but I suggest that its principle use is in terms of persons. In this sense, when you trust someone or something someone has made, you are doing something more than RELYING on the person to be predictable or EXPECTING a persons work to function as it has in the past. Trusting my students or them...

Does an interested layperson have any business in evaluating or criticizing the arguments of specialists in complex academic fields? Are the intellectual efforts of laypeople (limited, perhaps, for those of working-class status to only a few hours a week) destined to result in nothing more than the dubious ends of personal enrichment or cultural appreciation? Would it make more sense for someone of merely average cognitive ability and with only meager academic credentials to spend his free time watching mindless sitcoms or reading the latest potboilers rather than attempting to engage with cutting-edge scholarship across a variety of disciplines? Is our layperson in some sense obligated to accept the arguments and claims of experts if he cannot find reason to doubt them?

Excellent question(s). I suggest that in some areas of historical inquiry, trusting the "cutting-edge experts" in philosophy makes a great deal of sense (though not always). So, when it comes to dating and reconstructing which of Plato's dialogues were early or late, or what is the best available translations of texts, and the tracing of influence (how many ideas of Hume's were novel), it seems quite reasonable to "trust the experts." I suggest, however, that trusting expert philosophers on history is tricky when it comes to issues in which one's philosophical convictions might color one's judgment. So, a philosopher who is disposed to distrust utilitarianism, might be led to judge that the reason why Moism in China failed was because of the inherent limitations of such an abstract form of ethical teaching, when in fact that was not the reason why Moism did not have a longer life span. Moreover, when it comes to philosophers making claims that impact our daily lives, it may be that they are no less...

In many answers, here, philosophers talk about justified beliefs. I would like to ask if there is any difference between a justified belief and a rational belief.

There may be some difference insofar as a justified belief is usually considered a belief that is backed up by some evidence, and there may be times when it is rational (or not irrational or unreasonable) to have a belief even if one is quite uncertain about evidence. To use a homely example: You might have a vague feeling that you left your car keys back at the office and it would be rational for you to believe that is true (and go back to the office to check) even though your vague feelings don't count as sufficient evidence to make your belief fully justified. So, while there may be a difference, the two terms might be used interchangeably, especially if you hold what is sometimes called evidentialism, according to which the only beliefs that are rational and justified are those that you have evidence for. This is distinct from forms of what is sometimes called reliabilism, the view that a belief (even without evidence) may be justified if it is produced by a reliable means.

Hello. This submission will include two questions. The panelist´s are of course free to answer only one of them, if the other turns out to be of no interest. I´m no student of philosophy in the conventional sense, but lately it does consume much of my time. I remember reading Frege´s "The thought: a logical inquiry" a while back, and his answer to "an unusual objection" he thought he heard, puzzled me; "what if it were all a dream?" It seems to me that questions of this kind are unanswerable, and that Frege´s answer to this question is unsatisfactory. The (short) reason for this is simply that the question is one of fact, and one would have no possible way of empirically proving that one is not. What is your take on my objection? (I am aware that it is not one of the sections in the article that did the most impact on future philosophy) The second question relates to the distinction between analytic and extra-logical statements. After reading "Two dogmas of empiricism" by Quine, I am left wondering...

Thank you for these interesting reflections! As for your first point, there are a number of philosophers who address radical skepticism (e.g. can any of us know with certainty that we are not, as we seem to be, wide awake and acting in the world rather than, say, dreaming?) in the way you suggest. Arguably, life may continue just as it appears until one's death and yet there would be no decisive reason to rule out the possibility one was merely a brain in a vat. And because of this, some philosophers think that such radical skeptical hypotheses are idle or nonsensical or of no interest. I am somewhat of the other mind: I think we can imagine radical hypothetical states of affairs in which we are indeed systematically mistaken in almost all our beliefs about ourselves in the world (in brief, I think it conceivable that we might be in the matrix). While this does not have awesome practical consequences, I think it should humble us in our knowledge claims. As for the second point, Quine set out to...

Suppose I tell my friend that leprechauns don't exist. He responds: "Well, not in THIS realm, they don't. But they MIGHT exist in some hitherto undiscovered realm." To what extent does the claim 'X exists' depend on its being discoverable, or knowable? As a curious person, this question has really bothered me the past few days. There's something comforting about having knowledge, and that there might be an infinite amount of unknowables is rather disconcerting to me. Does Ayer's position -- that for a claim to be meaningful it must either be tautological or empirically veriable -- apply here? If someone could shed some light on this quandary, I'd be immensely appreciative. I really don't know my I allow myself to be bothered my these types of philosophical questions.

While Ayer's verificationism has gone out of fashion (he and others could not settle on a formulation of it that did not rule out science or some such apparently meaningful discourse) there are forms of what is called anti-realism which define 'truth' in terms of warranted assertability, which would rule out the possibility of there being truths that are out of reach from what we can know (at least in principle). Alas, there is a good argument against such a position in Thomas Nagel's work The View From Nowhere. One other idea to consider is that your friend may be right but in a way that has nothing to do with THIS (our) world. Some philosophers (David Lewis etc) have argued that there are indefinitely many POSSIBLE WORLDS. So, you might reply that, yes, leprechauns actually do exist but in a possible world not remotely related to ours! Check out Lewis's book on the plurality of worlds. It is awesome.

Can we ever truly understand another's point of view? When each one of us is made up of a different set of experiences and conditioning, and using the "trainings" of life we plug in answers to the perceived questions that surround us, can one really state without a doubt to understand another's mind? The answers might be the same but how we get to them is different, so is it in fact a different answer according to the individual? Sorry i know its a few different questions, but i feel the theme is there.

There are a few points to consider: first, the challenge of understanding another's point of view. Second, knowing without any doubt whatsoever another's point of view. The later is sometimes connected with what philosophers call the problem of other minds or, more recently, it has been called the zombie problem. How do you know that all of those around you who appear to be thinking, feeling, conscious persons are actually mindful, conscious beings? Could they all be zombies? Few philosophers worry about this as a real possibility but there are philosophers who think that such a state of affairs is logically (or metaphysically) possible (however unlikely) and this leads them to certain conclusions in their philosophy of human nature (sometimes such thought experiments have been used to argue that consciousness is something more than anatomy and behavior). In any case, I suspect it would be quite rare to come across someone who could not understand the points of view of other people. If we were...

What does it mean to say that it is impossible for there to be such a thing as a neutral, or objective, observer? When a person walks into a white room that it empty except for themselves and a chair, is asked to describe the room and says "It's a white room with a chair in it", it would seem that the situation they are in meets all the usual criteria for objectivity and neutrality. Certainly, it might be debatable whether the chair is a chair or a stool or a bench, and whether the white is really white or has been marred beige-grey by time, but either way, operating with a definition of chair and a definition of white, the conclusion is inevitable. So when philosophers say objective judgements are impossible, where do such banal statements about the physical world fall in?

There are some philosophers who think that human observations will always be from some subjective point of view. Indeed, modern philosophers have often thought that the secondary properties of objects (how an object looks, what it smells like, for example) will reflect the cognitive powers of observers. And some philosophers known as nonrealists will claim that there is no unique, "objective" description of the world. The white room with the chair might be described in terms of room or chair parts or as filled with only a slice of the spatio-temporal object of the room. But many philosophers in the past and today think that observations can be fair, free of bias and what one might call objective. I am pretty much in the realist camp and believe that "banal statements" can be assessed in terms of truth or falsehood in a pretty problem-free fashion. The state of affairs of 'There being a white room with a chair in it' is something that one can see and confirm. The fact that the very notion of a chair...

How can I persuade someone who is convinced that spiritual experience is the most reliable basis for establishing truth that empirical evidence is in fact more reliable?

Pray for them. Just kidding, though perhaps a prayer would not be uncalled for! I wonder if your friend is an extreme skeptic when it comes to empirical experience. Perhaps he is akin to Peter Unger in his book Ignorance, in which he seeks to undermine our confidence in our claims to know about ourselves and the world. Plato seemed to adopt a position not completely unlike your friend: he appers to have held that we may be more certain of the things of reason (mathematics, knowledge of the forms) than we can about the reliability of our senses. It is easy to have some sympathy with such an outlook: I am, for example, more convinced that 2+2=4 than I am convinced that I am not merely dreaming about the website AskPhilosophers. But your friend is in an usual position. Most of the philosophers who today defend the evidential role of religious (or spiritual) experience such as Richard Swinburne, William Alston, Jerome Gellman, Caroline Franks, K.M. Kwam, etc, argue for the reliability of such...

Pages