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Archive: Metaphysics & Epistemology

On a question of Mohan Matthen

Metaphysics & Epistemology · NewAPPS ·· More from August 2011

Mohan Matthen writes at NewAPPS:

p: I am sitting here writing a blog post. It is now later than when I wrote the previous sentence.

Can I doubt the truth of what I just wrote?

Let’s say I can rationally doubt p if there is some scenario S that falsifies p, and I cannot conclusively rule S false. Certainly there are admissible scenarios that falsify p: I may be dreaming. So I can rationally doubt p.

Let’s say doubt is sceptical if it spreads to unrelated propositions. The dream scenario falsifies p, but it also falsifies everything else I seem to perceive. Let’s say a doubt is empirical if it does not spread. I may doubt that my computer is working properly. But this doubt, based on the computer’s odd performance, does not spread to the proposition that my printer is working properly. (More details here.)

I would claim that I cannot empirically doubt p. I can doubt that it is now later than when I started writing, but only by dream scenarios and other sceptical stratagems that cast doubt on all contingent propositions.

p: I am writing a blog post. My fingers are above the keyboard. Can p be doubted?

In a way, no. But an Aristotelian would hold that up and down are absolute notions: ‘up’ is away from the center of the universe, ‘down’ is toward it.

Aristotelian ‘up’ and ‘down’.

The Newtonian says: no, ‘up’ is the direction toward the center of some nearby large mass, and ‘down’ is away from that center; ‘up’ and ‘down’ are notions of purely local application (and in some reference frames, simply inapplicable); the Aristotelians’ ‘up’ and ‘down’ is “overturned” as being, though conceivable, of no application anywhere.

As for ‘above’, “x is above y” will mean that y and x lie along a line incident with the center of the nearby mass that defines ‘up’ and ‘down’, and that y is farther from that center. So understood the relation ‘is above’ (new style) is coextensive with the relation ‘is above’ (old style). Moreover, various commonplaces about aboveness can be explained in the new system, e.g. that it takes effort to situate one thing above another, or that if y is above x then y, if left unsupported, will fall on x.

Can the Newtonian be said to doubt that her fingers are above the keyboard? Notice that in the exchange above, statements (or, for that matter, thoughts) in which the relation of aboveness figures have been given two interpretations. I want to emphasize both two and interpretation. The original thought—that my fingers are above the keyboard—is not interpreted, and not itself an interpretation of something else. It’s just there, as something I think or say (you could add: on the basis of certain experiences, but that doesn’t seem to advance the argument).

The two interpretations seem to be incompatible, or rather they seem to have incompatible consequences in a world in which there is more than one candidate for “nearby large mass”.

Newtonian up and down. In the region marked with a ?, ‘above’ and ‘below’ are not well defined.

The Aristotelian is committed to holding that if I am sitting on the visible side of the moon with my head pointing toward the Earth, my feet are above my head (‘above’ being understood Aristotelian-wise); the Newtonian is committed to holding that my head is above my feet (‘above’ being understood Newtonian-wise); and commonsense says that if x is (properly) above y, then y is not properly above x. (I have to bring in commonsense here, because there is no incompatibility between what the Aristotelian says and what the Newtonian says except through mediation by the “naïve” notion of ‘above’.)

My attitude toward my naïve belief that my fingers are above the keyboard cannot accurately be characterized as “doubt”. As a convert to Newtonianism, I am no more inclined to doubt that claim empirically than I was before I was converted (and whether I was converted from naïveté or from Aristotelianism). Newtonianism, like Aristotelianism, gives me an interpretation under which the claim is true.

On the other hand, I do, after a fashion, rationally doubt the claim insofar as I can imagine a scenario in which it, but also every other statement of a certain type, turns out false (e.g. if there were an even larger mass than Earth nearby and in the feet-to-head direction). Indeed, Newtonian physics gives me a systematic reason to relinquish the naïve notion of aboveness altogether insofar as it, along with various other notions about bodies and space, has a fatal connection with Aristotelianism (as many 17th-century philosophers thought it did). (The “retraining of intuitions” that Eric refers to was in part a relinquishment of Aristotelian/commonsense notions, e.g. of nonrelative rest and of differences between qualitative and specific change—alteration as contrasted with corruption. Descartes is quite explicit about this in Le Monde. Boyle in his Origin of forms and qualities devotes quite a bit of effort to convincing his reader that there is no distinction to be made between alteration, or change of quality, and generation and corruption, or change in substantial form; some of that effort consists in persuading his reader to give up Aristotelian interpretations of common experiences.)

I’m not sure whether commonsense notions of ‘before’ and ‘after’ stand to General Relativity as do commonsense notions of ‘above’ and ‘below’ to Newtonian (and post-Newtonian) physics. I suspect that in the world imagined by George Gamow, in which the speed of light is about 20 miles an hour, ‘before’ and ‘after’ would prove less useful, because simultaneity relations are not relativistically invariant. That would not lead me, exactly, to doubt that it is now later than when I wrote the previous sentence; but, as before, it would lead me to reinterpret what I take myself to mean when I make statements like that, and perhaps, in time, to relinquish ‘before’ and ‘after’. I would, for example, introduce the concept of worldline in interpreting commonsense notions of ‘before’ and ‘after’; and I would learn that those notions are applicable only along worldlines.

August 11, 2011

An identity not worth stealing?

Jeux d’esprit · Metaphysics & Epistemology ·· More from March 2007

Philosophers don’t need to worry just yet about being replaced by search engines. (Hat-tip: M)

Your query - who am I? - did not produce any search results at hakia.

Possible Reasons:

•There were no Web pages in hakia's reach that contained these terms.

•You may have misspelled the words beyond hakia's recognition skills.

•Your query is misspelled and in a Language other than English.

•You are playing a practical joke on us!

•There was an unusual technical problem.

Suggestions:

•Correct the spelling errors in your query.

•Rephrase your query using different words.

•Shorten your query by dropping off the least important terms.

•Try your query again sometime later in case of a temporary technical problem.

Material falsity

History of Philosophy · Metaphysics & Epistemology · Reading Notes ·· More from June 2005

What follows are some remarks inspired by Lili Alanen’s recent book, Descartes’s concept of mind. I haven’t reviewed the literature on material falsity, and make no claim concerning the novelty of what follows.

The phrase ‘material falsity’ appears in Meditations 3, in the midst of the first causal proof of the existence of God. The argument of that proof is that the idea of a perfect being, which the meditator finds in himself (and which therefore exists, in the manner in which things exist in thought) could have as its ultimate cause only a perfect being. I imagine that most readers will have encountered it.

June 18, 2005 | TrackBack (0)

Inebriate simian

Metaphysics & Epistemology · Philosophy of Philosophy ·· More from October 2004

Wednesday as I’m getting ready to leave I notice that the keys aren’t in the door. I look for them in the usual nearby places. There they aren’t. It occurs to me that I have been known to leave them hanging on the outside of the door. I look: aha keys. But since they’re outside, or so I say to myself, I still must find another key to open the door and retrieve them.

So I start looking again, cursing whoever removed the extras from the vase they’d been sitting in for six months (unless I removed them). Finally it dawns on me that if my keys are outside, and there are no others, then the door is not locked. Sheepishly (if it’s possible to be sheepish when alone) I pull the door open and grab them.

Sometimes I’m inclined to agree with those who call the mind a “drunken monkey”. Of all things we know, or think we ought to know, the mind best of all; and yet much of our mental discourse just happens, as events “outside” the mind just happen—events we neither control nor regard ourselves as being in any special position to know. Importance and availability make for fascination; opacity in the determination of thoughts makes for mystery. A mystery independent of “hard questions” and “explanatory gaps”, though perhaps referable to them. (It’s independent because even a dualist of the Cartesian sort might believe, as Malebranche did, that the nature of the mind is not known to us.)

October 24, 2004

Incidental thoughts on being oneself

Metaphysics & Epistemology · Psychology ·· More from August 2004

The last few weeks the word ‘slowly’ has popped into my thoughts at intervals, usually in between thoughts I consider my own. The phenomenon doesn’t seem different in kind from that of a persistent melody or fragment of music recurring in thought as a kind of background music. The occurrences of the word seem to have little to do with what I’m thinking at the moment; they just happen.

August 9, 2004

Sandwich Theory of Mind

Ethics · Metaphysics & Epistemology ·· More from June 2004

From the inimitable Fafblog. Bonus: a serious discussion of utilitarianism and deontology.

July 1, 2004

Là-bas… Les merveilleux nuages!

Metaphysics & Epistemology ·· More from May 2004

The American Midwest doesn’t do mountains or oceans. One thing it does do is clouds. This evening as I sat in the bay window on the second floor, looking northwest, the setting sun played off a cumulus cloud set against a background of thin cirrus. The trailing, western edge was pink and reddish-orange; the bulk of the cloud was grey, gradually darkening toward the east. A cloud thus illuminated has relief, it gains mass, becomes, however temporarily, a thing. Now the sun has set and the wind has taken it east, out of sight—across the river, perhaps.

You don’t need wind to make a cloud disappear. You can banish it with logic, using the sorites paradox.‡

May 11, 2004