To begin with a slightly pedantic point: logic doesn't actually give us very much knowledge at all. Logic tells us things like that, if A is true and B is true, then A & B is true. But, in order for us to be in a position to draw that conclusion, we first need to know that A is true and B is true. And, for most ordinary As and Bs, logic isn't going to tell us that. We need to turn instead to our senses. We have five external senses -- sight, touch, hearing, smell, taste -- which tell us about the qualities of objects in our environment. And, if we use these in a cautious and regimented way, and maybe start to draw logical inferences once we do first have the raw data to work from, then we can achieve an awful lot of knowledge.

But now to turn to your question: can meditation give us additional knowledge, besides that which we can get through the external senses? Yes, it surely can. Meditation can teach us what it feels like to meditate. Indeed, it might enable us to know quite a lot about our own internal psychological states. We usually don't pay a whole lot of attention to our own psychology... except when we make a deliberate effort to meditate upon it.

But can meditation operate as some kind of 'sixth sense', to give us knowledge about things outside ourselves? Frankly, I doubt it. That's an empirically testable hypothesis, after all, and I'm not aware of any studies that suggest that meditation can do this.

Some recent papers by the psychologist Daniel Kahneman suggest that we are not very good at predicting what will make us happy. It is a good idea to read these to get a feel for human fallibility.

Philosophers often argue that reflecting rationally on our values and goals can lead us to pursue what we "really" want, and thereby lead to greater satisfaction. You might try this and see whether it helps.

Some Buddhists, and some psychologists, argue that pursuit of a goal is more exciting than achieving it. They suggest focussing on the activity rather than the desired result.

Some recent papers by the psychologist Daniel Kahneman suggest that we are not very good at predicting what will make us happy. It is a good idea to read these to get a feel for human fallibility.

Philosophers often argue that reflecting rationally on our values and goals can lead us to pursue what we "really" want, and thereby lead to greater satisfaction. You might try this and see whether it helps.

Some Buddhists, and some psychologists, argue that pursuit of a goal is more exciting than achieving it. They suggest focussing on the activity rather than the desired result.

There's a lot of interest here, and a lot that's problematic in your questions! ... There are empirical studies in the U.S. at least that show things such as that college degrees increase average earning power over the course of your life -- now whether that means 'the more knowledge you have' leads to 'more success and happiness' I don't know, but it's the kind of statistic that might be relevant to your concerns .... I am not inclined to think that (all) knowledge is 'produced just to be sold' -- it's produced for many reasons, including the inrinsic interest of producing it -- but if it turns out that (much) knowledge is in fact useful, and valuable, then why would it be surprising that it would also be sold, even if it isn't produced for that purpose? Now if you're concerned about more political/sociological issues -- like what sorts of societies choose to have their education be so expensive, etc., that I can't say -- I too would prefer that education be far less expensive, be seen as a public right and not a privilege etc., but then that becomes an issue for politicians and not for philosophers ...

hope that's useful --

best, ap

p.s. the philosophers on this site don't get paid anythign for participating -- so not ALL knowledge is sold! :-)

According to the view that Berkeley is here criticising, there are, in effect, two worlds. Indeed, there are two corporeal worlds. There is an ideal world, constituted by perceptions that have been placed directly into our minds by God, and including perceivable tables, chairs, and even human bodies (including our own), complete with all of their familiar colours, textures, shapes, sizes and other sensible qualities. Then, distinct from and causally unrelated to this, and yet in some mysterious way corresponding to it, there is a world of material substances, including one that corresponds to our sensible body, but which cannot themselves be perceived, and which have no colours, no shapes, etc. Now, on this two-worlds view, how can we be so sure that our material bodies do survive? We can't perceive them, after all: how would we ever know? Maybe our material bodies got destroyed long ago: we'd be none the wiser, and it's not clear why we should even care, because God could perfectly well carry on giving our minds all of the same ideas, including those ideas that constitute our perceivable bodies.

Let's be clear: Berkeley is here criticising a particular form of realism, not simply criticising realism as such. Perhaps a realist might be on safer ground by maintaining that there really is just one corporeal world, but it's not the world of ideas (as Berkeley thinks), but rather the world of material substances. But then Berkeley reckons that he has plenty of arguments, elsewhere in his work, against that view: I have in mind all that stuff about primary and secondary qualities, coupled with the arguments concerning the abstractness -- and hence unintelligibility -- of the notion of some bare substratum behind all of these.

But Berkeley's system can indeed be regarded as a form of realism, to the extent that he does recognise a distinction between 'real things' and 'illusions' (and believes that the former really do exist). But real things and illusions, in his sense, are all still just ideas in my mind. Intrinsically, they are all on a par: the difference lies in their relations to one another. And his distinction is much as you have suggested: if I reach for an object, it's always there, unless I hallucinate. That is to say, when one idea coheres with other ideas in consistent ways that can be subsumed under universal laws of nature, then it constitutes a real body. If it fails so to cohere, then it's just an illusion, or an hallucination, or a figment of the imagination. See especially the Principles of Human Knowledge, sects. 30 and 33. As we come, through experience, to learn these laws of nature (laws that really just boil down to regularities in God's volitions), we can learn how to regulate our own behaviour for the sake of the preservation of our own bodies. But still, the bodies that we are seeking to preserve are the familiar ones that we know and love through our sensual experience of them, not any alleged colourless, shapeless, unperceivable and inefficacious material substances beyond these. Or, if you prefer, there is another way of preserving a notion of realism, one which does make it independent of my mind: we can say that the real world is the one that God himself perceives. But, even if that world is independent of my mind or yours, it will still not be independent of all minds; because, of course, Berkeley believes that God is a mind.

But I'm afraid I can't help you with Schopenhauer: I've never read him.

Your question engages the epistemology of testimony, which has recently gotten lots of attention among epistemologists.

But let's try to get a bit clearer on what the issue is. First, please understand that justification comes in degrees. If someone I don't know runs up to me and tells me that the president has been assassinated, I have some justification for believing it. But I certainly can't be said to know it, because that kind of testimony is not enough justification to "clear the bar." So epistemologists don't ever really accept that knowledge is justified true belief, where by "justified" they mean to count any level of justification as sufficient.

Secondly, one way to think about justification through testimony is to ask whether there is other evidence available. Back to my stranger telling me about the assassination. I notice that there is a TV store nearby and can see what is playing on the screens. I see no evidence of an assassination. Now how good is the justification the stranger provided? But if I see breaking news of an assassination, well...that is more (and more reliable) testimony (in most cases--not counting the "news" channels that really aren't!).

Finally, we might consider what we know about the source of the testimony. Do wwe have reason to believe that the person providing it has relevant expertise (such as a teacher)--or is it just heresay? So we need to judge the quality of the testimony and the qualifications of the one giving it. These are relevant to the question of how much justification the testimony confers.

Epistemologists sometimes distinguish between different kinds of knowledge, and then they debate whether all of these kinds really are different, or whether they can (some or all) be reduced to a single kind. The kind of knowledge you seem to have in mind is generally called "propositional" knowledge (where what is known is a proposition, such as 'the cat is on the mat' which you would probably count as a fact). Our cognitions of facts may have propositional content (this is sometimes also debated), or perhaps our cognitions of such things may be encoded in a different way--such as with a visual image, map, or blueprint, etc.) So some epistemologists prefer to talk about "informational" knowledge, rather than propositional knowledge, because perhaps the information that is known is not encoded propositionally. But anyway, I assume it is this sort of knowledge that you have in mind.

But I also think there are other kinds of knowledge that might be distinguished from "factual" knowledge. Here is one that has received lots of attention lately (though mostly from people in the philosophy of mind, rather than epistemology): Think about what it is like to have a headache. You know what that is like--but it what you know a fact? Well, it doesn't seem to be a proposition, or even propositionalizable. ("Having a headache is like ___.") Is it information? Well, perhaps, but the "encoding" involved seems to consist in having had the experience itself. If you have never actually had a headache, you won't know what it is like, and once you have had a headache, you will, and for that very reason. To have a headache is to know what it is like, and to know what it is like is to have had one. This doesn't quite look the same as other kinds of "factual knowledge." (By the way, there is an interesting conundrum that followwss from this sort of thought about God's alleged omniscience--Does God know what it is like to have a sinful desire? Hmmmm....)

Here's another: Do you know how to swim, ride a bike, change a tire? Most adults do. Isn't that a kind of knowledge? Seems so. But is it factual? Doesn't seem so--I could read a complete book listing all the facts about swimming or riding a bike and still not know how to do these things. (Another one here for God: Does God know how to ride a bike? Wouldn't ione need to have a body that is--at at least was at some time-- appropriately configured for a bike, and also have the actual experience/skill in order to know how? Not sure what to say about this one, either...)

One more kind of knowledge that is sometimees also considered is called "knowledge by acquaintance." Do you know Kim Yu-Na, the figure skater?" (I wish I did!) Not sure this really is knowledge, but we do talk about it as if it is.

Anyway, this may be a few examples to consider.

You say that love is an emotion, and in some sense we can grant that. But saying it suggests that love is a feeling, and that, in turn, suggests that it's like a warm sensation in one's tummy -- something that we can simply detect by introspection and that we can't (or can't easily) be wrong about. But it's more complicated than that. If I love someone, I can still have moments when I feel angry at them, for example. But my momentary anger -- a non-loving feeling -- isn't the same as not loving them. Love is, among other things, a complicated set of dispositions. Some of them are dispositions to feel a certain way in certain situations, and others are dispositions to behave in certain ways. I might be momentarily angry with my daughter, for example, but it might be true that if anything were to happen to her, I would be beside myself with grief. I might also be willing to make considerable sacrifices for her well-being. I might worry about her, take time to check up on her, and do all of this not just out of some sense of duty. Those dispositions are much better indicators of my love for her than my momentary feeling of anger.

On the other hand, if I wouldn't grieve the loss of my daughter, wouldn't go out of my way to help her, didn't care whether I spent time with her and so on, the fact that I would say I love her wouldn't count for much. Indeed, the fact that I believed I loved her might best be seen as a kind of self-deception due, perhaps, to my wanting to think well of myself. Similar comments apply to romantic love, of course.

Because love is a lot more than a feeling, people are quite capable of being wrong about whether they love someone. They can tell themselves that they don't love someone when they really do (think of someone who swears they no longer love their ex-lover when it's obvious to everyone else that they do), and they can tell themselves that they do love someone when they really don't. The connection with behavior is clear. If love involves dispositions to feel and to act, then the actions someone actually performs can be signs of their real dispositions.

Of course, this is only a small part of the story. The notion of love is both complicated and not entirely precise. It's certainly possible to love someone and yet not to be the jealous type. It's certainly possible to love someone and not be willing to go along with all of their wishes or principles; the examples you cite seem pretty clearly to be compatible with really loving someone. But if A treats B with reliable cruelty, for example, it would take a very complicated story to make sense of A's claim to really love B. This is so even if A really believes that s/he loves B.

The more general point is this: there are some things about our minds that we know better than others do. But there's a good deal about our minds that we can't discover just by introspection. We can be quite wrong about our selves in various ways. Add to that the fact that our psychologies have such an important role in producing our behavior, and it's not hard to see why sometimes others are in a better position than we are to make judgements about our own psychologies. The case of love is just one among many.