Just because God knows what is going to happen does not mean it has to happen, in the sense that human beings have to do what they end up doing. For example, I always have sugar in my coffee, if sugar is available, but that does not mean that I am incapable of having coffee without sugar. I used to smoke after a cup of coffee, but no longer do so, and here again I did not have to give up smoking. God doubtless knew what I was going to do before I did it, but the decisions to use sugar, and discontinue smoking all belong to me.

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.