I think I could do little better than to point you to what Descartes himself says about this. It's quite right that, in the First Meditation, he does seem to bring even logical (or mathematical) reasoning into the scope of his sceptical doubt: "What is more, since sometimes I believe that others go astray in cases where they think they have the most perfect knowledge, may I not similarly go wrong every time I add two and three or count the sides of a square, or in some even simpler matter, if that is imaginable?" (CSM II, 14; AT VII, 21). And then, at the start of the Second Meditation, we get the Cogito which, on the face of it, certainly seems to have the form of a logical deduction of existence from thought. So is he really entitled to it at all? Couldn't he similarly go wrong there too? Well, Descartes would say no, and the clue to his solution is to be found in the Second Replies: "when we become aware that we are thinking things, this is a primary notion which is not derived by means of...

It's quite true that Hume uses psychological terminology when setting out his position, even to the point of using the term 'idea' itself (alongside 'impression'). So, simply taken at face value, I'd agree that he does come across as a bit of an idealist. Nevertheless, probing more deeply, I would still want to resist that conclusion. For, the terminology notwithstanding, where I would be most inclined to take issue with your summary is in the claim that he regards these perceptions as being "wholly mind dependent". For something to be mind-dependent, I take it, the suggestion is that it couldn't exist without a mind. That certainly how a clear-cut idealist like Berkeley uses the term. But let's remember what Hume thinks the mind actually amounts to. It is, he says, "nothing but a bundle or collection of different perceptions, which succeed each other with an inconceivable rapidity, and are in a perpetual flux and movement" ( Treatise 1.4.6). So any given perception will be existing in a mind,...

The first thing to observe is that Descartes felt that the notion of 'unconscious thought' was incoherent. Maybe there can be neurological processes going on in the brain that we're not conscious of -- he would have no quarrel with that -- but, simply in virtue of the fact that there's no consciousness involved in the case, he would deny to these the title of 'thoughts'. If something is going to qualify as a thought at all, it needs to be a conscious thought. But then, what does 'conscious' mean? It means that these thoughts, when I have them, are accompanied by knowledge. And knowledge of what? Of the fact that I'm having them. "But", writes Descartes in the Second Meditation, "I do not yet have a sufficient understanding of what this 'I' is, that now necessarily exists." It's very easy to show that something exists: for, as soon as we think, we have this conscious awareness of the fact. But what exists? Answer: a thinking thing! And so that is what Descartes takes the pronoun 'I' to refer...

Aha! My answer seems to have crossed in the mail, as it were, with Charles Taliaferro's. Well, there you go, two for the price of one! The price, of course, being free: isn't this a lovely site?

That definitely doesn't sound like William James, on account of the use of the word "stress". The notion of stress, in what I take to be the relevant sense of the term, only really started to arise in the 1950s. But James died in 1910. That's the internet for you. He did however say the following, which might perhaps have inspired whoever it was that made up that quotation: "The great thing, then, in all education, is to make our nervous system our ally instead of our enemy . It is to fund and capitalize our acquisitions, and live at ease upon the interest of the fund. For this we must make automatic and habitual, as early as possible, as many useful actions as we can , and guard against the growing into ways that are likely to be disadvantageous to us, as we should guard against the plague. The more of the details of our daily life we can hand over to the effortless custody of automatism, the more our higher powers of mind will be set free for their own proper work. There is no more...

Before I address your question directly, it would be worth just running through Hume's main argument in section 10 of the Enquiry concerning Human Understanding , for the sake of those readers who might not have come across it before. Hume is concerned with the credibility of testimony concerning miracles. When we receive such testimony (in any form, whether received orally from one of our own contemporaries, or read in an ancient book), Hume asks us to weigh up the credibility of two competing hypotheses. (1) That the testimony is true, the laws of nature were violated, and the miracle really did occur as described. (Hume regards the violation of the laws of nature as being an essential, defining feature of a miracle. Others would define 'miracle' in other ways, and Hume's argument might not apply to them: but he is concerned with miracles as he defines the term). (2) That the testimony is false (whether through deliberate deceit or just through honest error), the laws of nature were not...

No, Descartes never called it an ontological argument. He wouldn't even have known what such a claim was supposed to mean, because the expression simply didn't exist in his time. The term 'ontological argument' was introduced (or at least popularised) by Immanuel Kant, more than a century after Descartes died. But would Kant, at least, have called it an ontological argument? No, because Kant -- and effectively everyone else who's used the term since him -- opted to use that term to denote a certain class of arguments for the existence of God, specifically, and Descartes (by his own admission!) was not God. So let's just put the terminology to one side: it's never a good idea to allow oneself to get hung up on jargon, when what we should really be looking at is the argument itself. Perhaps a better question to ask is this: does Descartes' "I think, therefore I exist" at least have a structure analogous to that which we find in those arguments for the existence of God that philosophers since Kant have...

First, let's consider what constitutes 'training'. Should we, for instance, be focusing solely on the subject(s) in which someone has taken a formal degree? It's true that Chomsky didn't formally study politics as either an undergraduate or a doctoral student: but then, neither did Machiavelli or Strauss. And Locke started out in medicine, Wittgenstein started out in engineering, David Lewis started out in chemistry, and, yes, Russell started out in mathematics. And so on. If we're going to dismiss them from the philosophical canon on those grounds alone, then we'd be losing an awful lot. What's more, if this was going to be our touchstone, then the career of any academic would be decidedly short: after ten or twenty years, their own field will have moved on from how it was when they first studied it, thereby rendering them ineligible to carry on working in it, at least without taking a second degree as a refresher course. But that would be a silly conclusion to draw. Better, I'd have thought, to...

Imagine there's a pure, disembodied intellect, and you somehow have the ability to communicate with it. It's a very clever intellect, so it's perfectly receptive to abstract, a priori mathematics: but it has never had any experience of spatial things, and it wants you to explain space to it. How might you go about this? Well, first you might explain the number line. You invite it to consider an infinite set of objects (we'll call them 'real numbers'), all different from one another, but continuously ordered in two directions from a particular element that we'll call 'zero' (or 'the origin'): ever greater to a positive infinity, and ever less to a negative infinity. And now, with the number line in place, you invite the intellect to take three such lines. That is to say, you invite it to consider an infinity of ordered triples of the form <x, y, z>, where x, y and z are all real numbers from this same set, but are capable of varying independently of one another. Let's call each of these triples a ...

'Formal' reality is a measure of the amount of perfection a thing actually has. Every existing thing has some formal reality, and the quantity of this reality depends on the kind of thing it is. (Putting it in traditional -- though not altogether Cartesian -- terms, it depends on its form ). God, if he exists at all, will have infinite formal reality, because the essence of God is to be an infinitely perfect being. Created substances will have considerably less formal reality than God, because it is in their nature to be contingent, dependent beings, limited and temporal, all of which connotes a degree of imperfection. And modes of those substances will have less still, because they are dependent not only on God but also on the substances whose modes they are. 'Objective' reality, meanwhile, only pertains to certain kinds of thing, namely those that have representational content. This might be a physical representation, e.g. a painting or a verbal description; or it might be a mental...

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 A s and B s, 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...