Early Modern Philosophy

Front 1

What did Descartes think could be called into doubt, and why? What did he think could be extricated from doubt, and why? Do you think his efforts at extrication succeed? And what was the point of the doubting in the first place?

Back 1

BACKGROUND MOTIVIATION

What’s Descartes’ Motivation for Doubting?
 Realizes that he has been mistaken in the past, and that the whole intellectual edifice built upon those mistaken beliefs is unstable.
 Wants to build a firm and lasting science, this requires firm, stable, indubitable foundations.
- doubt is a way of testing beliefs that might serve as a foundation
- anything doubtful, is not worth building upon; throw it out!
 attacking our current foundations take care of all beliefs built upon them
 if we doubt everything at first, it will not be possible to doubt what we later find to be true

What is the General Structure of Descartes’ Skeptical Argument(s)?
 If I don’t know that not-SH, then I don’t know that ordinary belief (O)
 I don’t know that not-SH
 Therefore, I don’t know O

Hint 1

SCOPE OF DOUBT

What are the Two Stages of Descartes’ Doubt? The Result?
 Doubt beliefs based on sensory experience (Dreaming Argument)
- includes all sciences based upon sense experience (physics, astronomy, medicine)
 Doubt beliefs not based upon sensory experience (Evil Genius)
- arithmetic, geometry and logic
 radical doubt ensues

What is the Dreaming Argument?
 Surely I can't doubt my senses when they tell me that I'm here, in this room, by a fire, wearing a bathrobe!
 But, my visual appearances are just as vivid as they are right now
- moreover, there is no definite sign that I am not dreaming
 So, I am not certain that I am not dreaming
 Therefore, since I might be dreaming, I should doubt everything that my senses tell me.
- I should also doubt all sciences that are built upon the senses (medicine, astronomy, physics)

What Survives the Dreaming Argument?
 even if my present sensory experience is a delusion, surely the individual elements of that experience exist.
- (painting example) imaginative scenes are painted by combining existing objects, shapes, colors, etc.
 so we can trust what our senses reveal to us about “corporeal nature in general, and its extension, the shape of extended things, the quantity or size and number of things, the lace in which they may exist, time, etc.”
 Arithmetic, Geometry, Logic Remain
- whether or not I am dreaming, 2+2=4 and a square has for sides.

What is the Evil Genius Argument? What does it Target?
 targets math, geometry, logic & anything else that survives the dreaming argument
 if I don’t know that I’m not the victim of an evil genius (SH), then I don’t know that O
- (here O is that which seems to be most clearly and distinctly true)
- if there’s a God, I could have the same sensory experiences, but with no corporeal substance, size, shape, etc.
- that God could also cause me to error any time I did simply arithmetic or geometry
 and if there is no God, isn’t even more likely that I would be deceived about my reasoning?
 I don’t know that ~SH
 Therefore, I must doubt everything

What Supports these Skeptical Arguments? (Evaluation)
 supported by closure conditions
- certainty is closed under (known) entailment
 (1) If I am certain that p and (2) p entails q and (3) I know p entails q, then (4) I am certain that q



EXTRICATION

How Does Descartes Begin to Extract Himself from Doubt?
 the proposition, “I am, I exist” is necessarily true whenever I say or think it.
- I am certain I exist even when I am doubting
 doubting is only one species of thought, I am certain I exist, no matter what I am thinking.
 “if I can be the author of my thoughts, should I not be something?”
 unlike my body and my hands, my thoughts cannot be separated from me in my mind.

Is the Cogito Argument an Inference? (Evaluation)
 In reply to the second set of objections, RD says that I exist is not something deduced by means of syllogistic reasoning, but by simple intuition.
 I think what’s intuited is his thought, and the validity of the inference to his existence. This comports well with RD’s teachings about intuitions in his Regulae: we intuit the things that make deductions possible. (see Rule III.)

EVALUATION

Is there a valid form of the Cogito Argument? (Evaluation)
 Using exists as a predicate: For all x, if Thinks(x), then Exists(x). There is an x such that Thinks(x) and x = ego. Therefore ego existo.

Would An Act Besides Thinking Suffice for the Cogito Argument? (Evaluation)
 Technically, yes; but …
 RD focuses on thinking because he is not sure there are any other acts. (See Fifth Objections and Reply.)

Is Descartes’ Entitled to Think that He Exists? (Evaluation)
 E.g., Russell, History of Western Philosophy, objects that RD’s is not entitled to think he is thinking, but only that there are thoughts—from which his existence does not follow.
 Russell is ignoring the subjective character of experience; he is supposing that there is nothing to the experience of, say, pain over and above the hurt. But this is false. There is the for-me-ness of the pain. This is an aspect of experience, too; viz., no one in pain has to inquire as to whose it is.

Front 2

What is the Cartesian Circle? How did Descartes get into it? Do you think he got out? [How does your answer to the last question impact your overall assessment of the Meditations? (Buras)]

Back 2

What is the Cartesian Circle?
 (1) Descartes argues from C&D premises (CDIs)  to the conclusion that a non-deceiving God exists
 (2) Descartes then argues from the premise that a non-deceiving God exists  the conclusion that what is perceived C&D is true.
 The Worry of Vicious Circularity: he presupposes that all CDIs are true in order to prove that all CDIs are, in fact, true
- (he is presupposing that whatever is perceived C&D is true in order to prove that, in fact, whatever is perceived C&D is true.)

How Does Descartes Get Into the Circle?
 Med. II Descartes is certain that he exists because he C&D perceives that in order to think, he must exist
 Med. III, he wants to make the general rule that whatever is perceived C&D must be true
 but, he recalls that he’s been made to doubt CDIs before, like 2+2=4 (Evil Genius Arg.)
 therefore, in order to be certain that his CDIs are true, he needs God [i.e. ~Evil Demon]
 the problem: in arguing for God, he uses premises that the Evil Genius Arg. appears to undermine
- (i.e. his argument is viciously circular—it presupposes the truth of CDIs in order to prove that CDIs are true)

Why Might the Circle not be Vicious (How Might Descartes Escape)?
 Descartes two-steps: while the argument appears circular, it actually consists of two independent steps, or ‘arcs’
 these ‘arcs’ refer to two levels of knowledge:
 (1) Descartes’ uses his CDIs to achieve knowledge1 of the principle that all CDIs are true
 (2) Upon achieving knowledge1 of this principle, Descartes’ is then able to upgraded his CDIs to knowledge2

What Allows Descartes to Use His CDIs as Premises?
 he cannot help but assent to these CDIs while perceiving them
- (e.g. 2+2=4, a square has four sides)
 thus, they provide a lower-level of knowledge (knowledge1)
- S knows1 (cognitio) that p, if S clearly and distinctly perceives that p
 [note: it is important that RD has yet to establish any principle about the certainty of all CDIs]

Why Does Descartes Only Have Knowledge1 of His CDIs?
 because of lingering hyperbolic doubt
- he can doubt his CDIs when not attending to them
- (the evil genius can make him doubt the reliability of his faculties)

What is Required for Knowledge2?
 Descartes must also clearly and distinctly perceive (know1) that all CDIs are true
 S knows2 (has scientia) that p if:
- (A) S clearly and distinctly perceives that p, (knows1¬ that p)
- and (B) S c&d perceives the principle that whatever S c&d perceives is true. (knows1 ‘the principle’)
 establishing this principle requires getting rid of the evil demon / lingering hyperbolic doubt
 thus, he needs to prove that a non-deceiving God exists

Hint 2

Outline Step #1 of theTwo-Step
 1. using C&D premises, Descartes argues that a non-deceiving God exists
 2. from this conclusion he derives the epistemic principle that whatever he perceived c&d is true
- (for all p, if he clearly & distinctly perceives that p, then p)
 3. Descartes now knows1 that all his CDIs are true
- that is, while he thinks about this principle, he cannot help but assent to it
- yet when he does not, he could doubt it; the worry of the evil genius could return

Outline Step #2 of the Two-Step
 1. Descartes has knowledge1 that whatever is perceived c&d is true
- (he knows1 that there is no evil genius; a non deceiving God exists)
 2. So, at the same time, Descartes perceives c&d that (a) there is no evil genius and (b) all of his CDIs are true
 3. thus, all his CDIs are upgraded to knowledge2
- (he now has true knowledge (scientia) that all of his CDIs are true)
 the solution: Descartes has shown that CDIs are self-supporting
- (they remove the only reason for doubting them.)

What is the Textual Support for the Two-Step?
 Atheist Geometer (Reply to the 2nd Set of Objections)
 know1:an atheist can be clear & distinctly aware (cognitio) of geometric truths
 "The fact that an atheist can be ‘clearly aware that the three angles of a triangle are equal to two right angles’ is something I do not dispute.”
 knowledge2: but this awareness (knowledge1) is not true knowledge (scientiam)
- this is because his awareness (knowledge1) can be called into doubt [i.e. lingering hyperbolic doubt]
 thus, the atheist geometer can never be certain that he is not being deceived even about CDIs like geometric truths.
- (he may not always be aware of this doubt, but he will never be completely free of it (have scientia / knowledge2) until he believes in God)

What is a Critique of the Two-Step?
 it’s not exactly clear how step #2 escapes the evil genius’ grasp
- (why can’t I later doubt the principle that all my CDIs are true?)

How Might You Defend the Two-Step?
 perhaps Descartes thinks that as soon as you c&d perceive that there is no evil genius, he disappears forever.
- (there is no longer a reason for lingering hyperbolic doubt; you have removed the only reason for doubting CDIs)
- “And such knowledge will remain true, even if I forget the reasons which lead me to the conclusion” (Med V).
 even if you do come to doubt your knowledge2, you can restore your confidence in it by rehearsing the Meditations

Based Upon the Cartesian Circle, What is Your Overall Assessment of the Meditations?
 the Circle highlights the perennial question of bootstrapping: how can we ever prove the reliability of our own faculties?
 by requiring himself to answer this question, Descartes sets a awfully high bar
 over the bar: he gets out of the circle, and proves that our faculties reliably assent to truth
 under the bar: he might still demonstrate that our faculties reliably assent to CDIs (esp. math, geom., logic)
- this could have been accomplished with only the Dreaming Argument
- the Evil Genius is what gets him into trouble (or illustrates that bootstrapping is impossible)
 his attempts to get rid of the evil genius do illustrate how hard it is to give up CDIs
 if he set a lower bar:
- he would not be able to set indubitable foundations for the sciences
- but, maybe CDIs are good enough
 (after all, Descartes thinks they are good enough to get us to knowledge of God’s existence)

Front 3

Compare and contrast the understanding of substance in Descartes with Locke and Spinoza or Leibniz.

Back 3

What are RD’s 4 Dualisms?
 substance: infinite/finite
 finite substance: thought/extension
 properties of finite thinking substances: intellect/will
 effects: free/non-free

Descartes: Substance
 an independently existing thing
Descartes: Infinite Substance
 completely independent
- independently existing and independently conceived
 all else depends upon it for existence
 only one: God

Descartes: Finite Substance
 qualified independence
- independent from other finite substances (existence & conceptual)
- but dependent upon infinite substance (existence & conceptual) conceived independently of other finite substances
Descartes: Two Kinds of Finite Substances
 thinking substances (unextended things)
- indivisible
 material substances (extended things; bodies)
- infinite divisible
 (note: RD takes divisible/indivisible to be a further indication of the Real Distinction)
Descartes: the essence of (finite) substances
 the principle attribute of a substance
- thus, what distinguishes substances from one another
 all other properties are referred to this attribute
- (everything that exists is either a substance or an attribute of a substance)
Descartes: Thought
 the essence of a thinking (unextended) substance
- willing/perceiving cannot be understood apart from thinking
Descartes: Extension
 the essence of a material (extended) substance
- all other modes (features) must be understood in terms of extension
Why is Extension the Essence of Matter?
 because a body can lose any of its properties, except extension, without ceasing to be a material body
 cf. the wax: it retains its extension along w/mutability/flexibility
- but this is simply a mode of extension—an ability to change one’s shape
Descartes: Two Properties in Thinking Substances
 Intellect: “Through the intellect alone I merely perceive ideas, about which I can render judgment” (42b).
 Will: “willing is merely a matter of being able to do or not do the same thing” (43a).
Two kinds of effects:
 Free: the will is free to choose or not choose A
 Non-free: the intellect cannot help but perceive what is present to it

What is the Problem with RD’s 4 Dualisms?
 they make his system un-rationalistic; different things can play by different rules
- two ‘rules’ for substances (Spinoza jumps on this)
- two ‘rules’ for how thinking substances behave (the two effects)
- two ‘rules’ for the interaction of finite substances
 purely physical (physics)
 [possibly] divine fiat (mind/body)
 “the nature of man could have been so constituted by God that that same motion in the brain would exhibit something else to the mind” (Med. VI).
- two ‘rules’ for independence: shouldn’t conceptual also imply causal independence (Spinoza)
Descartes: One Extended Substance or Many?
 Descartes says, extended non-thinking stones and non-extended, thinking persons are substances (Third Meditation, 44).
- Is a stone its own material substance?
- Or is it part of one large material substance?
 (This is the one stuff vs. many things interpretative problem)
Reasons for the One Extended Substance Interpretation
 all physical change is simply due to matter in motion
 but, there is no empty space; all matter is extension
 so, bodies must move in a ‘circle’—constantly displacing/shifting one another
 the picture: material bodies comprise one continuous, extended whole, moving as if in a whirlpool.
 thus, it seems as if there is really only one extended substance: the material universe as whole
Descartes’ Influence on Spinoza
 Descartes’ geometrical conception of physics leads to a picture of the material world that is one continuous, extended whole, moving as if in a whirlpool.
 thus, there is really only one extended substance—the material universe as a whole.
 strictly speaking, particular bodies should not themselves be called substances
- (they are modes of one extended substance)
 bodies are simply differentiated by the ways in which matter moves.

Hint 3

Spinoza – Monist, no finite substance
There is only one type of substance. And it is infinite. Thought and extension are two of an infinite number of attributes of it.
Ethics I.D3: “By substance I understand what is in itself and is conceived through itself, that is, that whose concept does not require the concept of another thing, from which it must be formed.”
Substance = what is independently existing AND self-explanatory or conceptually independent.
Conceptual Independence = Ontological Independence
Attribute = “that which the intellect perceives as constituting the essence of a substance (D.IV).”
Mode = “the modifications of substance, or that which exists in, and is conceived through, something other than itself (D.V).”
God is the only substance. Michael Della Rocca’s Arg from Todd’s notes is worth memorizing.
A. The Argument for monism: Four step interp (drawn from Michael Della Rocca, Spinoza, Routledge, 2008).
1. No attribute sharing (Ip5).
a. Two things must differ in some feature in order to be distinct. (Identity of Indiscernibles.)
b. Differences in mode could not explain differences in substance, because substance is prior to modes (1p1). So it must be the attributes to distinguish.
c. Suppose there are two substances with the same attribute.
d. Then that attribute would signify the same essence in two distinct substances. Contradiction.
e. Hence there is no difference between two substances with the same attribute.
f. So there is only one substance per attribute.
2. Substance exists (Ip7).
a. No substance can be caused by anything else (Ip6c).
b. If it were, it would have to be conceived through its cause.
c. And in that case it would not be a substance.
d. So substance must be produced by itself (Ip7d).
3. God—a substance with all attributes—exists.
a. God is by definition a substance (Id6).
b. God has every attribute
a. There is nothing in virtue of which a substance fails to have every attribute by the PSR.
b. So, a substance has every attribute.
c. It pertains to the nature of a substance to exist (Ip7).
d. So God exists; indeed, God exists necessarily.
4. Therefore, No other substance exists.
a. If another substance existed, it would have to have some attribute (1p10s).
b. But God has all the attributes.
c. So any substance other than God would have to share an attribute with God.
d. But attribute sharing is impossible.
e. Therefore no substance other than God exists.

Locke – Realist about substance in general and particular spiritual and material substances (along with their primary qualities), BUT a conceptualist/conventionalist about secondary qualities and sortals
“Pure substance in general” & “ideas of particular sorts of substance”
1. Substance in general: “that which stands under,” and “I know not what”; the unknown support under qualities/properties that cannot subsist by themselves; bare substratum
a. Locke thinks that while we cannot perceive substance in general, we must posit material substance to explain our sense experience of external objects and spiritual substance to explain our experience of our mental life.
b. Berkeley criticizes this supposition in the case of matter.
c. Hume criticizes the supposition in the case of matter AND spirit.
2. Particular Substances – independently existing things
a. Corporeal Substance (315a)
i. Primary qualities – they are in bodies themselves; e.g. solidity, extension, figure and mobility
ii. Secondary Qualities – they are only powers of bodies to produce sensation in us; e.g. color, sounds, and tastes
b. Finite Spiritual Substance (316b) – characterized by modes of thought
i. Locke writes: ”First, Modes I call such complex Ideas, which however compounded, contain not in themselves the supposition of subsisting by themselves; such are the words signified by the Words Triangle, Gratitude, Murther, etc.“ (II. xii.4, p. 165) Locke goes on to distinguish between simple and mixed modes.
c. Infinite Spiritual Substance (God): A certain “enlargement” of our idea of ourselves.
3. Sortals: these are the ideas we have of particular substances’ essences by which we sort them into distinct substances. These are a product of our understanding, and as such are only nominally essences and not the real essences of the things.
a. Hence, contra Aristotle and substantial form, the essence of a species with regard to our knowledge is only a nominal essence (constructed by our association of primary qualities with substance in general). Locke doesn’t deny that particular substances have real essences, just that we can’t know them.
i. For example, God, spirits and body have separate essences which we cannot understand.
ii. But the seeds of skepticism are sown and Hume will reap the harvest.

Front 4

Leibniz – Monads, infinite and created substances

Back 4

Leibniz rejects Spinozism because it entails that God is limited to what is actual. However, God contains in his mind all possibilities. So what is actual cannot be identical with God. Leibniz said that “Spinoza simply said out loud what Descartes was thinking, but did not dare express.” Descartes view of substance entails Spinoza. Since Spinoza’s view is false, so is Descartes’.

The nature of substance “is to have a notion so complete that it is sufficient to contain and to allow us to deduce from it all the predicates of the subject to which this notion is attributed (DM 8).”
But Leibniz does not, like Arisotle, think that being the subject of predication is sufficient for substance-hood. Rather, Leibniz believed that a substance had a “complete individual concept” and that it was essentially an active unity endowed with perception and volition (SEP). What is a complete individual concept?
“An individual substance or of a complete being is to have a notion so complete that it is sufficient to contain and to allow us to deduce from it all the predicates of the subject to which this notion is attributed.” (A VI iv 1540/AG 41)
Actions and passions belong to individual substances.
An accident is what does not include everything that can be attributed to the subject.
To illustrate the difference between substance and accident, Alexander the Great is a king. “Alexander the great” is a substance. Being a “king” is an accident.
Monads – simple substances
1. Every property of a monad is an essential property – it has no accidental properties)
2. Each Monad reflects the whole universe from its perspective
3. Monads have no “windows”
4. Perception and appetition belong to monads.
Is Alexander the Great a monad? As far as I can tell, his soul is a monad and his body is composed of many monads.
The substances of Soul and Body act in pre-established harmony.

Hint 4

Dan’s notes on Leibniz are very helpful.
(1) Metaphysics: Substance
a. Substance: a substance is something which has “a notion so complete that it is sufficient to contain and to allow us to deduce from it all the predicates” that apply to it (DM 8) – a complete individual concept. Accidents don’t have such a notion. Only substances exist as distinct beings; accidents exist in substances. All this follows from the PIN definition of truth: if substances didn’t have a complete notion, there would be truths pertaining to the substance whose predicates aren’t contained in their subjects.
b. Results of this notion of substance:
i. Unity: it follows that substances are not merely aggregates, but have a closer sort of conceptual unity – they are true unities, or monads.
ii. Mirror of the universe: since each substance contains in its notion each and every predicate it has had, has, or will have, it is within itself a kind of perspectival mirroring of the whole of reality. It contains relations to everything in the world. At any given time, then, there are “marks” or “traces” within the substance of all its relations and qualities.
iii. Pre-established harmony: since each substance or monad contains within itself the reason (a conceptual reason) for all its states, there is no genuine causal interaction between monads – that is, monads are “windowless” – because no monad’s activity can provide the reason for truths involving another monad. So the apparent causal interaction between monads must be in fact a kind of harmony pre-established by God. The coherence of the various monads’ concepts is the result of God’s creative activity.
iv. Substances can begin and end only by creation and annihilation (follows from lack of causal interaction between substances – only God’s activity can explain existence or non-existence of substances). Also, substances cannot be divided or combined, since they are complete notions within themselves.
v. Substances are immaterial – material, extended bodies are not candidates for substance. The reason is that they don’t contain the sort of complete concept that is necessary for substance. Body is therefore one of the accidents of substance, a kind of perception, tied up with the perspective of each monad.
c. Modality – there is a problem with modality, since this conception of substance seems to collapse necessary and contingent truths. Leibniz’s solution involves God essentially. Both necessary and contingent truths have a priori proofs, because they have a sufficient reason for their existence. Necessary truths, though, are proved a priori simply by virtue of the principle of contradiction, without reference to God’s will (depend only on the understanding). The a priori proofs of contingent truths involve truths about God’s will – which possible substances he chooses to actualize. This is enough, thinks Leibniz, to distinguish contingent from necessary truths, even if God (because of the PSR) always chooses the best. (Contingent truths, then, depend not just on understanding but on God’s will.) Another way to draw the distinction is that necessary truths have finite a priori proofs, because we can get down to the primitive notions and discern any contradiction, while contingent truths have infinite a priori proofs, because you have to go through the infinite series of contingent explanations of a contingent fact, and then go outside the series for the explanation of the whole series in terms of God’s choice conforming to the PSR and the principle of the best. (By contemporary standards, this doesn’t really get you truly contingent truths.)
d. Final and efficient causes – Leibniz wants to harmonize the modern emphasis on efficient or mechanistic causation with the pre-modern emphasis on final causation. Final causation, he thinks, isn’t useful for the details of physics and often represents a kind of cop-out. Efficient causation, though, is inadequate for explaining some deep metaphysical truths, like God’s action in creating the world. To put this another way, bodies (as perceptions of substances) act according to efficient causation, where souls (the substances themselves) are only explainable in terms of final causation. These are harmonious. So final and efficient causation are compatible and complementary.

Front 5

Sketch an interpretation of the Meditations in accord with the above quotation (to Marsenne, (not included, but the quotation is about how the Meditations contains the foundations of Descartes’ new anti-Aristotelian physics). What elements constitute a defense of a new (anti-Aristotelian) physics (MI)?

Back 5

Elements of a defense in Meditations
1. No occult-like qualities/ formal causation – rather simple impact causation
2. “There is nothing in the intellect that was not first in the senses” vs. Withdraw from the senses
3. Explanations that are clear and indubitable vs. unknown agent’s purposes
4. Success in the sciences, masters and possessors of nature vs. endless debate

Hint 5

Background to the Meditations:
The Scientific Revolution of the 17th Century

I. The Hermeneutical Key to the Meditations: I may tell you, between ourselves, that these six Meditations contain all the foundations of my physics. But please do not tell people, for that might make it harder for the supporters of Aristotle to approve of them. I hope that readers will gradually get used to my principles, and recognize their truth, before they notice that they destroy the principles of Aristotle. --Rene Descartes, Letter to Mersenne, 18 January 1641 (p. 2)

II. The Aristotelian-Scholastic Synthesis
A. The Hylomophic Theory of Corporeal Substance: bodies are layer-cakes, made from these ingredients
1. Prime Matter: the stuff of material things.
2. Substantial Form: makes a material thing what it is; essence.
3. Quantitative Form: gives a material thing its size.
4. Qualitative Forms: accidental features of things.
B. Forms as Causes
1. Immanent Cause of changes in things that have them; e.g., the form of an oak causes the acorn to grow into a tree.
2. Transeuent Cause of changes in things that don’t have them. Causes acquisition of a form; e.g., the form of heat in a fire propagates itself in nearby things.
3. The contagion model of (formal) causation
a. posits “occult” qualities
b. broadly psychological (purposive) understanding of forms’ influence; Descartes called them “little souls”
c. long on the why; short on the how
C. The Case of Sense Perception
1. The qualitative forms in, say, an apple make it red
2. The redness of the apple propagates itself in a medium
3. The sense organs receive the form from the medium
4. The mind receives it from the sense organs
5. Note the Qualitative integration: one thing is in the apple making it red and in my mind making me think of red

III. The Corpuscularian Alternative
A. The Defining Thesis of the Modern Physics.
1. Negatively: Banishment of formal causes; no occult qualities
2. Positively: “the phenomena of the world are physically produced by the mechanical properties of the parts [i.e., tiny corpuscles] of matter and that they operate upon one another according to mechanical laws” (pp. 262-3).
3. The Impact Model of Causation
a. non-purposive explanations
b. requires contact
c. results determined solely by mechanical properties (size, shape, hardness, motion)
4. Qualitative Alienation: the physical vs. the mental
a. The real world is characterized by mechanistic features; other features are metaphysically demoted (See Galileo reading.)
b. Demotion motivated by causal relevance doctrine: The real qualities of bodies are those that make some difference. Given the impact model, only the mechanical properties make a difference.
c. Demotion codified in the 1-2 distinction—Hume later called this the defining thesis.
d. Leads to the veil of perception doctrine: When we look at the world, what we see is colored, etc. The real world is not. So what we see when we look at the world is not the real world.
e. “Universal Error” requires some explanation; raises the specter of radical skepticism; Descartes request that readers “withdraw from the senses.”
B. The Case for Corpuscularianism (from Boyle reading)
1. Perspicuity: The principles of explanation (and hence the explanations offered) are easily understood; The difference making features can be quantified, the explanations modeled on geometry (as opposed to psychology). “The world is God’s epistle … written in mathematical characters” (pp. 268).
2. Extensiveness: wherever there is physical change there has got to be some means of physical change—viz., “If an angel himself should work a real change …” pp. 266)—and the means of physical change will be explicable in terms of matter and motion. Nothing slips the net. (This is also Boyle’s answer to the biggest obstacle to the corpuscular hypothesis.)
3. Strong on the hows. The mechanist answers “how come?” not by citing some agent’s purpose (the why), but by citing the local impact (the how)—and this is what the mechanist thinks inquiring minds want to know (pp. 265).
4. Other arguments (not from Boyle reading)
a. Parsimony: Little souls aren’t needed.
b. Success: especially in terms of prediction;
i. I think this is the real factor in the meteoric rise of the modern physics.
ii. In many other areas, the modern philosophy has not proven too easy work out and the Aristotelians have some real advantages.