blog.kennypearce.net

Descartes, Cudworth, and God

Ren. Cartefius, (though otherwise an Acute Philosopher) was here no less Childish, in affirming, that all things whatsoever, even the Natures of Good and Evil, and all Truth and Falsehood, do so depend upon the Arbitrary Will and Power of God, as that if he had pleased, Twice Two should not have been Four, nor the Three Angles of a Plain Triangle, Equal to Two Right ones, and the like...Than which, no Paradox of any old Philosopher, was ever more Absurd and Irrational: and certainly if any one did desire, to perswade the World, that Cartesius, notwithstanding all his pretences...
Continue reading "Descartes, Cudworth, and God"

Berkeley on the Phenomenology of Mathematics

Nor do I think [abstract ideas] are a whit more needfull for enlargment of Knowlege, than for Communication. For tho' it be a point much insisted on in the Schools, that all Knowlege is about Universals, yet I can by no means See the necessity of this Doctrine. It is acknowledg'd that nothing has a fairer title to the Name of Knowlege or Science than Geometry. Now I appeal to any mans thoughts, whether upon the entrance into that Study, the first thing to be done is to try to conceive a Circle that is neither great nor small, nor...
Continue reading "Berkeley on the Phenomenology of Mathematics"

Al-Ghazali on Skepticism

I'm currently reading Al-Ghazali's spiritual/philosophical autobiography for the first time. The translation I found in the library gives the title as Freedom and Fulfillment, but the book is better known in English as Deliverance From Error. I'm sure this has been noticed before, but the discussion of skepticism near the beginning of the book can be interestingly compared with some of the well-known discussions of skepticism in European philosophy. Here's a quick outline. Al-Ghazali states that he is looking for a kind of "certain knowledge" that will guarantee "safety from error" (§8). He recognizes that "the dicta of authority" (i.e.,...
Continue reading "Al-Ghazali on Skepticism"

Ibn Sīnā and Descartes on the Nature of Body

Thus, a body is such an entity that, if one posits a longitude on it, another longitude will be found intersecting it at a right angle, and a third longitude of these two lengths will stand as a perpendicular on the point of the previous intersection. Whatever can be placed under these three magnitudes in the aforesaid manner and is also a substance is called a body ... But that which is in a body, such as length, width, and depth, is known to exist not in the form of the body, but as an accident to it. For instance,...
Continue reading "Ibn Sīnā and Descartes on the Nature of Body"

Two Varieties of Occasionalism

As Elisabeth of Bohemia famously pointed out, Descartes appears to be committed to the following inconsistent triad: In every instance of causation, there is an a priori conceptual connection between cause and effect. There are no conceptual connections between mind and body. Mind and body interact causally. The most common response to this problem among Descartes's 17th century followers was occasionalism, the view that bodily phenomena do not genuinely cause mental phenomena but are merely reliably correlated with them, and vice versa, so that bodily phenomena may be called occasions of mental phenomena and mental phenomena may be called occasions...
Continue reading "Two Varieties of Occasionalism"

Philosophy and Trust in the Senses, from Montaigne to Berkeley

I want to begin this post with a longer sequence of quotations than is usual. The reason is that simply juxtaposing the quotations goes a long way toward telling the story I want to tell. Here, then, is a sequence of comments on philosophy and trust in the senses, ranging in date from 1580 to 1713: We want to find out by reason whether fire is hot, whether snow is white, whether anything within our knowledge is hard or soft. There are ancient stories of the replies made to the man who doubted whether heat exists—they told him to jump...
Continue reading "Philosophy and Trust in the Senses, from Montaigne to Berkeley"

Descartes and the Rise of the 'New Philosophy'

Earlier this year, Christia Mercer published a fascinating article on the influence of Teresa of Avila on Descartes. Mercer shows (in my view convincingly) that the structure of Descartes's Meditations is patterned after Teresa's The Interior Castle, an extremely popular text at the time, especially in Jesuit circles such as the college where Descartes was educated. This line of influence has been missed by scholars because philosophers are dismissive of women and of religious mystics, and Teresa was both. (I hasten to add: scholars are often quick to forget that certain male philosophers such as Plotinus and Augustine were undeniably...
Continue reading "Descartes and the Rise of the 'New Philosophy'"

Princess Elisabeth's Refutation of Descartes

I also find that the senses show me that the soul moves the body, but they teach me nothing (no more than do the understanding and the imagination) of the way in which it does so. For this reason, I think that there are some properties of the soul, which are unknown to us, which could perhaps overturn what your Metaphysical Meditations persuaded me of by such good reasoning: the nonextendedness of the soul. This doubt seems to be founded on the rule that you give there, in speaking of the true and the false, that all error comes to...
Continue reading "Princess Elisabeth's Refutation of Descartes"

"What Descartes Doubted, Berkeley Denied, and Kant Endorsed"

I've posted a new draft, "What Descartes Doubted, Berkeley Denied, and Kant Endorsed," to my writings page. This is actually a rewrite of a much older paper; the original idea pre-dates my dissertation. In it, I argue (among other things) that Kant's fundamental complaint against Berkeley is that Berkeley's empiricism leaves him with cognitive resources too sparse for the construction of a genuine world. In particular, Kant targets Berkeley's rejection of the application of the concept of substance to perceived objects. Of course, in Language and Structure I argue that Berkeley is aware of these sorts of problems and develops...
Continue reading ""What Descartes Doubted, Berkeley Denied, and Kant Endorsed""

Between Incredulity and Superstition

A little essay on pedagogy I wrote is going out in the upcoming Lilly Network Communique. The essay takes off from the Berkeley quote that's been in the header of this blog for some time, so I thought I'd make it available here too. Between Incredulity and Superstition A Pedagogy of Uncertainty "Religion," George Berkeley once remarked, "is the virtuous mean between incredulity and superstition"(Alciphron, §5.6). In the context of Berkeley's Alciphron, this is little more than a throwaway line, but to me it suggests a promising account of an important intellectual virtue. I believe that growth in this virtue...
Continue reading "Between Incredulity and Superstition"

Quote of the Day: Margaret Cavendish on Rational Animals

That all other animals, besides man, want reason, [Descartes] endeavours to prove in his discourse on method, where his chief argument is, that other animals cannot express their mind, thoughts or conceptions, either by speech or any other signs, as man can do: For, says he, it is not for want of organs belonging to the framing of words, as we may observe in parrots and 'pies, which are apt enough to express words they are taught, but understand nothing of them. My answer is, that one man expressing his mind by speech or words to another, doth not declare...
Continue reading "Quote of the Day: Margaret Cavendish on Rational Animals"

A Brief History of Christian Conceptions of the 'Soul'

It is sometimes said that Christianity presupposes the existence of a soul, that, due to the progress of science, this view is no longer credible, and that, therefore, Christianity can no longer be taken seriously. It is very probable that there are some combinations of views, widely held among self-identified 'Christians', which can be effectively criticized along these lines. However, there are several puzzling features about this line of thought. The first is that it is not clear what the relevant 'progress of science' is supposed to be. Neuroscience is indeed advancing, but it can hardly be considered so advanced...
Continue reading "A Brief History of Christian Conceptions of the 'Soul'"

Locke and Berkeley on Cartesian Skepticism

Descartes's First Meditation is one of the most striking texts in the history of philosophy. As anyone who has taught the text can attest, students are immediately gripped by the problem, and often despair of a way out. John Locke was evidently not such a student, for he responds to these doubts primarily with ridicule: If any one say, a Dream may do the same thing [as sense perception], and all these Ideas may be produced in us, without any external Objects, he may please to dream that I make him this Answer, 1. That 'tis no great matter, whether...
Continue reading "Locke and Berkeley on Cartesian Skepticism"

True and Immutable Natures in Descartes's Ontological Argument

In the Fifth Meditation, Descartes argues that "from the fact that I cannot think of God except as existing, it follows that existence is inseparable from God, and hence that he really exists" (CSM 2:46). Caterus famously replied with the 'existing lion' objection (parallel to Gaunilo's 'Lost Island'): we can't think of anything as an existing lion without thinking of it as existing, so the existing lion must exist (CSM 2:72). In fact, Caterus didn't need to add 'existing' at all: existence is a necessary condition for the exemplification of any property whatsoever. Nothing can be red, blue, five feet...
Continue reading "True and Immutable Natures in Descartes's Ontological Argument"

Philosophers' Carnival 103

The 103rd Philosophers' Carnival is now up at Philosophy, etc. with a link to my post on seeing the world through teleology-colored glasses. Also of interest in the new philosophers' carnival is Chris Hallquist's discussion of reformed epistemology and moral realism. In the course of his discussion, Chris gives a narrative of the history of early modern philosophy which is similar to my Berkeley-centric narrative (despite not mentioning Berkeley): Descartes sets up an impossible program, Hume shows that either Cartesian or classical empiricist assumptions lead inevitably to skepticism, and this motivates a 'Reidian' program...
Continue reading "Philosophers' Carnival 103"

A Berkeley-Centric Narrative

Continuing the discussion of the historiography of modern philosophy, I want to consider an alternative narrative. The standard narrative is Kant-centric: the rationalists and empiricists spend a century squabbling, then Kant comes along and figures out what's right and what's wrong with each view, resulting in the Critical Philosophy. The key figures, apart from Kant, are Descartes, the great founder of the rationalists; Locke, the great founder of the empiricists; and Hume who called attention to the severe failings of both schools. (When I took intro to modern at Penn, this is exactly the way it went: these were the...
Continue reading "A Berkeley-Centric Narrative"

Alternative Groupings of Early Modern Philosophers

Last month, there was some blog discussion about historiography and teaching methods in early modern philosophy. The standard story is evidently due to Hegel, and continues to be standard despite being unpopular among specialists in history of modern. It groups modern philosophers before Kant as follows:

Rationalists Descartes Spinoza Leibniz

Empiricists Locke Berkeley Hume

Dana McCourt, blogging at The Edge of the American West...
Continue reading "Alternative Groupings of Early Modern Philosophers"

Quote of the Day: A Source in Descartes for Berkeley's Visual Language Theory?

We must take care not to assume - as our philosophers [i.e. the scholastics] commonly do - that in order to have sensory awareness the soul must contemplate certain images [i.e. the species] transmitted by objects to the brain; or at any rate we must conceive the nature of these images in an entirely different manner from that of the philosophers. For since their conception of the images is confined to the requirement that they should resemble the objects they represent, the philosophers cannot possibly show us how the images can be formed by the objects, or how they can...
Continue reading "Quote of the Day: A Source in Descartes for Berkeley's Visual Language Theory?"

How Putnam Defeats Descartes' Demon

A little while back, I wrote a post describing Cartesian demon skepticism as a form of 'adversarial epistemology'. The idea is that Descartes' thought experiment can be conceived of as a game with two players: the meditator and the demon. The meditator selects a process for forming beliefs from perceptual experiences, and the demon knows what process the meditator has selected, and controls all of the perceptual experiences. If the meditator ends up with mostly true beliefs, she wins. Otherwise, the demon wins. Now, I mentioned at the bottom of that post that this way of framing the problem is helpful...
Continue reading "How Putnam Defeats Descartes' Demon"

Cartesian Demon Skepticism as 'Adversarial Epistemology'

In one of my computer science classes in undergrad, we discussed a particular way of thinking about the efficiency of an algorithm, which the professor called 'adversarial upper bounds'. The idea was to suppose that someone knows the 'guts' of your algorithm - exactly how it works - and that person is trying to make your algorithm take as many steps to complete as possible. The upshot was that sometimes with this kind of system inserting some randomness will give you a better expectation value. For instance, suppose I am trying to find a route (just any route) from A...
Continue reading "Cartesian Demon Skepticism as 'Adversarial Epistemology'"

Three Varieties of Certainty

'Certainty,' whatever that is supposed to be, would certainly (!) seem to be important in epistemology. Like a lot of important words, it frequently gets thrown around without definition. I know of at least three totally distinct ways of using this term, and the only thing they all seem to have in common is 'very high epistemic status' - i.e. something is certain if we really know it, in some way that is 'better' (more certain!) than ordinary knowledge. I'm going to outline here these three different varieties of certainty. Cartesian Certainty (also called 'demon-proof certainty') is attributed to a...
Continue reading "Three Varieties of Certainty"

Descartes, Berkeley, and Moore on the Existence of the Spiritual and the Physical

I have been thinking recently about Moore's argument for the existence of the physical world.
For those who may not be familiar, Moore's argument looks something like this:

1. Here is one hand; here is another
2. If there are two hands here, then two hands exist.
3. Hands are physical objects
4. Therefore, physical objects exist

This simple argument seems to be part of the reason why many contemporary analytic philosophers do not consider idealism a live issue (something that I intend to make it my business to change). However, it seems to me to have two enormous and equally simple defects:

1. It isn't actually an objection to Berkeley's theory, since Berkeley accepts all of the premises and the conclusion.
2. Most people who make this argument are physicalists but if you accept the argument then, by parity of reasoning, you must allow Descartes to prove the existence of the soul.

Continue reading "Descartes, Berkeley, and Moore on the Existence of the Spiritual and the Physical"