Reid Against Skepticism

Transcription

1 Thus we see, that Descartes and Locke take the road that leads to skepticism without knowing the end of it, but they stop short for want of light to carry them farther. Berkeley, frightened at the appearance of the dreadful abyss, starts aside and avoids it. But the author of the Treatise of Human Nature, more daring and intrepid, without turning aside to the right hand or to the left, like Virgil's Alecto, shoots directly into the gulf Reid Against Skepticism 1. The Skeptical Project: Reid sketches the progression of the skeptical project of the modern era, from Descartes to Hume (a contemporary of Reid). Briefly: Descartes introduces the Method of Doubt, finds that he is certain of nothing except his own existence. Yet, ultimately, Descartes concluded that we could still know that objects exist as we perceive them (via his proof of God s existence). Locke distinguishes between primary and secondary qualities, and argues that the sensations of secondary qualities do not resemble anything in the objects, and exist only in our minds. Yet, bodies still have primary qualities as we perceive them. Berkeley, using Locke s arguments, concludes that the sensations of PRIMARY qualities ALSO do not resemble anything in the objects themselves, and exist only in minds. So, material bodies are reduced to an unintelligible nothingness. Yet, Berkeley did not even think to question the existence of other immaterial beings (God, and other minds). Further, by invoking God, he concluded that we could still be confident in the regularity and continued existence of things in the world. Hume accepts all of the above, but undermines also the concepts of causation and laws of nature, as well as the proofs for God s existence. He doubts other minds He even doubts the persistence of his OWN mind over time, saying that perhaps he is nothing more than a bundle of sensations! This is full-blown skepticism. Yet, Hume admits that he does not live it; rather, he must ignore it all in his daily life. Metaphysical Lunacy: This path toward complete skepticism is a necessary result of the Cartesian system, Reid says. Modern philosophy has led us into metaphysical lunacy. If this is wisdom, let me be deluded with the vulgar! 2. Matter as a First Principle: So, what went wrong? Two things. Let s look at the first. The First Principle of Modern Philosophy: First, note that there is one tenet that was NOT questioned by the modern philosophers: That our thoughts, our sensations, and everything of which we are conscious, have a real existence, is admitted in this system as a first principle, but everything else must be made evident by the light of reason. From Descartes to Hume, no one ever doubted their APPEARANCES the inner, mental world of impressions. But, why stop there? Can t we call even those into doubt? No, says the skeptic. Why not? Because they cannot help it. You see, EVERY system has to take 1

2 SOMETHING as a given. There must be SOME starting point. (For instance, NONE of these philosophers ever thought to question the law of non-contradiction; i.e., the axiom which says that any assertion of the form <P and Not-P> cannot possibly be true.) All reasoning must be from first principles. And for first principles no other reason can be given but this: That, by the constitution of our nature, we are under a necessity of assenting to them. Reason can neither make nor destroy them, nor can it do anything without them. A mathematician cannot prove the truth of his axioms, nor can he prove anything, unless he takes them for granted. A historian or a witness can prove nothing unless it is taken for granted that the memory and senses may be trusted. A natural philosopher [which, during Reid s time, included philosophy AND science] can prove nothing unless it is taken for granted that the course of nature is steady and uniform. Note that we choose our first principles based on a NECESSITY. Certain assumptions about reality impose themselves on our minds, and we cannot proceed without them! First Principles of Common Sense: But, says Reid, belief in the external, material world is just as unavoidable and necessary as our belief in our conscious experiences. On Reid s view, the very nature of sensation includes with it a judgment or belief in the real, external existence of the thing being perceived. He writes, every operation of the senses, in its very nature, implies judgment or belief, as well as simple apprehension. When I perceive a tree before me, my faculty of seeing gives me not only a notion or simple apprehension of the tree, but a belief of its existence, and of its figure, distance, and magnitude; and this judgment or belief is included in the very nature of the perception. Belief in the existence of external things is not something we DEDUCE from our experiences. It is not as if we are inside of our heads examining mere images or representations, and then say to ourselves, A-ha! These images must be images of THINGS that are really OUT THERE! No. Rather, belief in the existence of external objects is just a given a part of the very nature of what it is to have sensations. For instance, if I experience a pain in my toe, I am not MERELY experiencing bare ideas; i.e., as if I am having a mere pain-seeming and a mere toe-seeming. Rather, these sensations point BEYOND themselves to the actual EXISTENCE of a toe, and are NECESSARILY accompanied by a BELIEF in the toe s existence. This belief isn t arrived at via reason. Rather, it is a natural and irresistible accompaniment of perception. In short, the existence of an external world should be included among our first principles. 2

3 How or when I got such first principles upon which I build all my reasoning, I know not, for I had them before I can remember. But I am sure they are parts of my constitution, and that I cannot throw them off. That our thoughts and sensations must have a subject, which we call our self, is not therefore an opinion got by reasoning, but a natural principle. That our sensations of touch indicate something external, extended, figured, hard or soft, is not a deduction of reason, but a natural principle. The belief of it, and the very conception of it, are equally parts of our constitution. If we are deceived in it, we are deceived by him that made us, and there is no remedy. The Role of Reason: When we pursue knowledge and reason, the end-goal is not to tear down all that we thought we knew by doubting even the seemingly most firm of presuppositions. Rather, the role of reason is to RECONCILE and MAKE SENSE of those things which are, by necessity of our very nature, immediately most obvious and apparent to us! As belief in an external world is among those things whose acceptance are necessitated by our very nature, we should do our best to reconcile reason to it: it is better since we cannot get rid of the vulgar notion and belief of an external world, to reconcile our reason to it as well as we can. In short, in order to reconcile philosophy with our unavoidable common sense notions, we must take the existence of the external world as a GIVEN. It must be one of our STARTING principles not something to be proven. (Consider also that the modern system was a movement to REPLACE the Medieval system, which was seen as absurd. Material objects mysteriously impressed themselves upon our minds, making our minds literally take on the exact FORM of those objects, as happens when a seal is pressed upon hot wax. But, is that really MORE absurd than a system which rejects the existence of material objects!?) 3. Direct Realism: Reid is arguing in favor of common sense. The universal assumption of everyone other than the skeptical philosophers is that, when we have sensations, we are directly sensing THINGS out there in the world. The skeptics claimed instead that what we directly perceive are merely some mental IMAGES or REPRESENTATIONS of things but never the things themselves. Reid says that the skeptics have taken this Representationalist Theory of Perception (or, as he calls it, the Ideal System ) as a given, such that anyone who believes otherwise must produce their proof. But, Reid believes that he has shifted the burden of proof back onto the Representationalist. How in the heck does it make MORE sense to say that what we directly perceive are mere IMAGES of things rather than THINGS? 3

4 [Note: Though Reid doesn t quite put his finger on it, he may have some inkling of the following worry: It almost seems as if the Representationalist is saying that there are little images inside of my head, and that *I* am the thing who LOOKS AT those images. Like this: But, then, how do I perceive those images? Won t I somehow have to observe them? (e.g., with some sensory faculty?) If so, then isn t it really the case that I don t perceive the images directly, but rather some IMAGES OF those images? But, wait Then, etc. And we re off on an infinite regress. Like this: Long story short, it s not obvious that a Representational account of perception is any clearer than an account which states that we observe objects DIRECTLY.] Descartes and those after made one huge mistake: The error I mean is that we can know nothing about body or its qualities but as far as we have sensations which resemble those qualities. Reid protests: to my apprehension, I immediately perceive external objects ; that is, we DIRECTLY perceive objects, UNmediated by the senses. 4

5 Against the Table Argument: Recall that both Hume and Berkeley argued that, because the sensation of the size and shape of a table change in the observer, while the actual size and shape of the table are supposed to be things that do NOT change, it must be that size and shape are only ideas in the mind too (just like secondary qualities). To Reid s mind, this was supposed to be the best evidence against the view that we directly perceive objects, immediately. Reply: Imagine that there really IS a table out there, and we DO directly perceive it. What would we EXPECT our perception of it to be like? Reid says, Tell me the REAL, objective size and shape of the table. Then give me some location outside of that table. With this information, we can calculate with certainty the exact apparent size and shape of the table which any observer in that location would perceive! Asks Reid: Is not this a strong argument that it is the real table you see? The apparent magnitude of the table changes depending on the observer s location, sure. But, given how geometry works, what else would you EXPECT to happen!? [Reid s Thought Experiment: Reid thinks that we come to know that there are external objects by perceiving their primary qualities. But, we seem to perceive them in a very mysterious way neither by sensation NOR reflection. Consider: The Blind Man: Imagine a blind man who begins as a blank slate. We give him various sensations ONLY of touch: e.g., we prick him with a needle; then press something against his skin; then drag an object slowly across his skin; and so on. Would such a person acquire the ideas of extension or motion? Reid thinks not. Such experiments may give a certain succession of feelings as the colic may do but no feelings nor any combination of feelings can ever resemble space or motion. (Reid s focus on touch here is no coincidence. Think about it: Taste, smell, and hearing are ONLY ever the perception of secondary qualities. Sight and touch are the only means by which one can perceive primary qualities; i.e., that there IS in fact an external, extended, solid thing in the world. But, clearly, blind people still come to know about the sizes, shapes, and motions of external objects. So, sight isn t REQUIRED. Thus, a blind person has only ONE inlet through which they might perceive primary qualities namely, touch. By focusing on such a case, Reid hopes to gain a better understanding of how this happens.) So, we have these ideas of primary qualities like size, shape, and motion. Those before Reid all held that ALL of our ideas were ultimately just sensory experiences (or else experiences of mental operations like doubting, believing, etc.). But, Reid believes that he has just shown that the ideas of size, shape, and motion are NOT identical to or 5

6 reducible to any sensory experience. Neither do they seem to be obtainable by inward reflection. Yet, we have them! (But, recall, sensation and reflection were supposed to be the ONLY two ways in which we can acquire ideas!) So, where in the heck did they come from? Reid thinks that experience must, in some cases, directly access things themselves so that we have experiences of qualities that are not themselves identical to any sensation. (Recall that, above, he said that external objects just sort of assert themselves, by their very nature imposing a belief in their external existence; and also imposing ideas of primary qualities like size, shape, and motion upon us.) Reid believes himself to have refuted those before him: Extension, figure, motion If any one of them can be shown to be an idea of sensation, or to have the least resemblance to any sensation, I lay my hand upon my mouth, and give up all pretense to reconcile reason to common sense in this matter, and must suffer the ideal skepticism to triumph. But if, on the other hand, they are not ideas of sensation, nor like to any sensation, then the ideal system is a rope of sand, and all the labored arguments of the skeptical philosophy against a material world and against the existence of everything but impressions and ideas proceed upon a false hypothesis. Reid concludes: Our conceptions of extension, shape and motion are not ideas of sensation or of reflection, so the mere fact that they exist overturns the whole ideal system by which the material world has been tried and condemned. The conception of extension, motion and the other attributes of matter can t be the effect of error or prejudice; it must be the work of nature. And the power or faculty through which we acquire those conceptions must be something other than any power of the human mind that has been explained by philosophers up to now, because it isn t sensation and isn t reflection. ] Conclusion: Reid thinks he has demonstrated that we DO in fact perceive external objects DIRECTLY (for, something external imposes ideas of primary qualities as well as belief in external objects upon us). This view is called Direct Realism. Contrast this with Descartes and Locke, who were Realists that is, they DID believe in the existence of external objects but they believed that we never perceive those objects directly. (Rather, we only ever perceive the ideas that they cause in us.) This is Indirect Realism. Then there is Berkeley s view. Berkeley REJECTS the existence of external objects, so he is not a realist. Rather, his view is Idealism, or the view that all that external objects are merely ideas. These ideas (and the minds that perceive them) are all that exist. Next time, we will examine Immanuel Kant s view, who in a way marries all three of these views together into Empirical Realism / Transcendental Idealism. 6