by Corry Shores
[Search Blog Here. Index-tags are found on the bottom of the left column.]
[Hume, Enquiry concerning Human Nature, entry directory]
[The following is summary. Any boldface in quotations or bracketed commentary is my own. Proofreading is incomplete, so there are still typos present. I apologize for the distractions. Block quotations of this text are copied from the Project Gutenberg online text. Paragraph enumerations follow those of the print text.]
David Hume
An Enquiry concerning Human Nature
Section IV:
Sceptical Doubts concerning the Operations of the Understanding
Part II
Brief summary:
We have knowledge either of {1} relations of ideas, which are logically certain (because their contraries imply contradictions), as for example mathematical equations, or we have knowledge of {2} matters of fact, which are probable, because their contraries are not contradictions, as for example ‘the sun will rise tomorrow’ (for, it is not a contradiction to think, ‘the sun will not rise tomorrow’). We trust such conclusions regarding matters of fact, because we come to have knowledge of causal relations governing such regularities. And this causal knowledge is obtainable only through experience. The basis of this kind of knowledge is the assumption that like causes produce like effects, and thus that the future will resemble the past. We once ate bread and learned it was nourishing. Then when seeing other bread-like things, we are more likely to infer they will be nourishing, with each uniform experience pushing us more toward drawing that conclusion. Suppose there really was a cognitive path going from the premises to the inductive conclusion. There would be then one form of reasoning or another that allows us to make that intermediary step. But there are only two kinds of reasoning, and neither makes this allowance. One kind is demonstrative reasoning, which concerns the relations of ideas and whose conclusions are necessary on account of the absurdity of their negations. But inductive sorts of conclusions are not logically necessary. The only other sort of reasoning is moral reasoning, which concerns matters of fact and existence. Here however the conclusions are only probable. But we cannot use moral reasoning to ground inductive reasoning, because it itself uses inductive reasoning; we cannot say that inductive reasoning can be trusted on account of it having proven to be reliable in the past, because we would be using an inductive principle for our justification, where it is that very inductive principle we are trying to find justification for. But there also is no deductive reasoning to draw these conclusions about the future. To understand why, we consider an illustration. Suppose you eat one egg. It has a certain taste. Then we eat a hundred more on other occasions, with each case giving the same taste. After that uniform series, we conclude without much hesitation upon seeing another egg that it will have that same taste. But when we ate an egg the second time, we were not nearly so quick to draw that conclusion. We instead waited to see. So were there some deductive reasoning to allow us to draw this conclusion about its taste, it would have been available to us from the first instance, allowing us to infer immediately that all forthcoming instances will be the same. And it is not enough to say that we trust them just because they are reliable enough for our practical purposes. For, this does nothing to explain the reasoning underlining how the inferences are made in the first place. One might object that this reasoning for inductive inferences exists, but we just have not found it yet. However, we can be sure that it does not exist, because creatures incapable of rational thinking (like infants and animals) have no problems drawing such inductive inferences.
Summary
4.2.14
[Our knowledge of matters of fact is based on knowledge of cause and effect, which in turn is based on experience. But what is the basis for reliable knowledge of experience?]
[In the prior section, we noted there are two sorts of objects of human reason or enquiry. The first kind are relations of ideas. They are always certain on account of logical necessity, as their negation is inconceivable. An example are mathematical formulas. The other kind are matters of fact. They are possible, and not certain, on account of their contrary claims being conceivable, as in, “the sun will rise tomorrow.” Yet we trust much of our knowledge in matters of fact. This is because we assume that they are governed by laws and relations of cause and effect, which hold consistently. We also determined that no knowledge of cause and effect can be deduced a priori but rather must be discovered by experience.] We now wonder, what is the basis for us to to draw reliable conclusions from experience?
But we have not yet attained any tolerable satisfaction with regard to the question first proposed. Each solution still gives rise to a new question as difficult as the foregoing, and leads us on to farther enquiries. When it is asked, What is the nature of all our reasonings concerning matter of fact? the proper answer seems to be, that they are founded on the relation of cause and effect. When again it is asked, What is the foundation of all our reasonings and conclusions concerning that relation? it may be replied in one word, Experience. But if we still carry on our sifting humour, and ask, What is the foundation of all conclusions from experience? this implies a new question, which may be of more difficult solution and explication. Philosophers, that give themselves airs of superior wisdom and sufficiency, have a hard task when they encounter persons of inquisitive dispositions, who push them from every corner to which they retreat, and who are sure at last to bring them to some dangerous dilemma. The best expedient to prevent this confusion, is to be modest in our pretensions; and even to discover the difficulty ourselves before it is objected to us. By this means, we may make a kind of merit of our very ignorance.
(online / 23)
4.2.15
[Knowledge from experience, as we will see, is not based in reasoning.]
Hume will not here tell us what such knowledge from experience is based on. He will only explain that we know it is not from reasoning or other cognitive processes.
I shall content myself, in this section, with an easy task, and shall pretend only to give a negative answer to the question here proposed. I say then, that, even after we have experience of the operations of cause and effect, our conclusions from that experience are not founded on reasoning, or any process of the understanding. This answer we must endeavour both to explain and to defend.
(online / 23)
4.2.16
[Our knowledge of matters of fact involves an inductive inference that things with like sensible features have like causal properties. We assume that all things looking identical to bread have similar nourishing powers. But while we can know this causal feature holds in the past occasions we experienced, it is not obvious how we can be certain about future ones. The grounds for this inductive inference are obscure.]
Our senses only give us superficial properties of objects, like color and weight, but they do not tell us the kinds of “powers and principles” behind the object’s causal capacities. So we might see that bread is brown and weighs some small amount, but we cannot from those data know it has the capacity to nourish a human body. And we can observe bodies moving, but we cannot see the inertia itself. However, whenever two things have the same observable features, we are quick to conclude they have the same causal powers. So when seeing something that looks identical to bread, we infer it has the same nourishing power. Now, we can be sure that in the prior and first instance that the bread was nourishing. But Hume wonders how we can infer in future instances of objects with similar features that they will be nourishing too. [For, as we noted, its nourish powers are not given in the features. So those features alone are not an adequate indication. We need some other mental operation to extend the findings of the prior instance to the future one.] Hume says there is some “medium” connecting past observations with inferences about future ones. He does not know what that is, but those who think it does exist and is the source of conclusions on matters of fact must produce it.
It must certainly be allowed, that nature has kept us at a great distance from all her secrets, and has afforded us only the knowledge of a few superficial qualities of objects; while she conceals from us those powers and principles on which the influence of those objects entirely depends. Our senses inform us of the colour, weight, and consistence of bread; but neither sense nor reason can ever inform us of those qualities which fit it for the nourishment and support of a human body. Sight or feeling conveys an idea of the actual motion of bodies; but as to that wonderful force or power, which would carry on a moving body for ever in a continued change of place, and which bodies never lose but by communicating it to others; of this we cannot form the most distant conception. But notwithstanding this ignorance of natural powers6 and principles, we always presume, when we see like sensible qualities, that they have like secret powers, and expect that effects, similar to those which we have experienced, will follow from them. If a body of like colour and consistence with that bread, which we have formerly eat, be presented to us, we make no scruple of repeating the experiment, and foresee, with certainty, like nourishment and support. Now this is a process of the mind or thought, of which I would willingly know the foundation. It is allowed on all hands that there is no known connexion between the sensible qualities and the secret powers; and consequently, that the mind is not led to form such a conclusion concerning their constant and regular conjunction, by anything which it knows of their nature. As to past Experience, it can be allowed to give direct and certain information of those precise objects only, and that precise period of time, which fell under its cognizance: but why this experience should be extended to future times, and to other objects, which for aught we know, may be only in appearance similar; this is the main question on which I would insist. The bread, which I formerly eat, nourished me; that is, a body of such sensible qualities was, at that time, endued with such secret powers: but does it follow, that other bread must also nourish me at another time, and that like sensible qualities must always be attended with like secret powers? The consequence seems nowise necessary. At least, it must be acknowledged that there is here a consequence drawn by the mind; that there is a certain step | taken; a process of thought, and an inference, which wants to be explained. These two propositions are far from being the same, I have found that such an object has always been attended with such an effect, and I foresee, that other objects, which are, in appearance, similar, will be attended with similar effects. I shall allow, if you please, that the one proposition may justly be inferred from the other: I know, in fact, that it always is inferred. But if you insist that the inference is made by a chain of reasoning, I desire you to produce that reasoning. The connexion between these propositions is not intuitive. There is required a medium, which may enable the mind to draw such an inference, if indeed it be drawn by reasoning and argument. What that medium is, I must confess, passes my comprehension; and it is incumbent on those to produce it, who assert that it really exists, and is the origin of all our conclusions concerning matter of fact.
(online / 24-25)
4.2.17
[We will examine all the branches of knowledge and see that none can ground the inductive inferences we make regarding matters of fact.]
[So we do not know what allows us to make the inductive inference. Hume will now delineate all the branches of knowledge to show that none allow us to make such inferences. (This will allow us to know that the inference is not based on any rational principle.)]
This negative argument must certainly, in process of time, become altogether convincing, if many penetrating and able philosophers shall turn their enquiries this way and no one be ever able to discover any connecting proposition or intermediate step, which supports the understanding in this conclusion. But as the question is yet new, every reader may not trust so far to his own penetration, as to conclude, because an argument escapes his enquiry, that therefore it does not really exist. For this reason it may be requisite to venture upon a more difficult task; and enumerating all the branches of human knowledge, endeavour to show that none of them can afford such an argument.
(online / 25)
4.2.18
[The are two kinds of reasoning: 1} demonstrative reasoning (which concerns the relations of ideas) and {2} moral reasoning (which concerns matters of fact and existence). Matters of fact do not involve demonstrative reasoning, because there is no contradiction in thinking that objects will have different properties in the future.]
Hume divides all sorts of reasoning into two kinds: {1} demonstrative reasoning and {2} moral reasoning. Demonstrative reasoning concerns the relations of ideas. [In the explanatory notes at the end, the editor defines demonstrative arguments in the following way.
demonstrative arguments: arguments that lead with total logical certainty from premiss(es) to conclusion, such as valid arguments in mathematics. See §10 of the Introduction, above.
(Peter Millican. “Explanatory Notes”, 191)
And from the editor’s Introduction:
Demonstrative reasoning is what can be loosely called ‘deductive’ reasoning, in which the steps of the argument proceed with absolute certainty based on the logical relations between the ideas concerned (e.g. the kind of argument used in mathematics, such as the proof of Pythagoras’ Theorem). Factual reasoning—which Hume also calls ‘moral’ and Locke had called ‘probable’—is now commonly called ‘inductive’ inference, encompassing all sorts of everyday reasoning in which we draw apparently reasonable (but less than logically certain) conclusions based on our personal experience, testimony, our understanding of how people and things behave, and so forth.
(Peter Millican. “Introduction”, xxxvii)
So inductive inference regarding matters of fact does not involve demonstrative argumentation, because the conclusions do not follow by logical necessity. This means also that the negation of the inductive inferences imply no contradiction.]
All reasonings may be divided into two kinds, namely, demonstrative reasoning, or that concerning relations of ideas, and moral reasoning, or that concerning matter of fact and existence. That there are no demonstrative arguments in the case seems evident; since it implies no contradiction that the course of nature may change, and that an object, seemingly like those which we have experienced, may be attended with different or contrary effects. May I not clearly and distinctly conceive that a body, falling from the clouds, and which, in all other respects, resembles snow, has yet the taste of salt or feeling of fire? Is there any more intelligible proposition than to affirm, that all the trees will flourish in December and January, and decay in May and June? Now whatever is intelligible, and can be distinctly conceived, implies no contradiction, and can never be proved false by any demonstrative argument or abstract reasoning priori.
(online / 25)
Moral reasoning concerns matters of fact and existence.
4.2.19
[Our inductive arguments about the future can only be probable. And we cannot justify this sort of reasoning by saying that we may trust them because they often prove true. For, this is using circular reasoning by employing an argument based on probability to justify arguments of this very same kind.]
[I am not certain, but the next points seem to be the following. Inductive arguments about the future can only have more or less probability of being true. I do not understand what is meant by “arguments concerning existence”. It is apparently an idea we already addressed, but it does not seem to simply mean an argument based on a premise saying that something exists or having a conclusion make such a claim. Maybe it means an argument dealing with an actual situation rather than a general statement of law concerning any situation. I am not sure. At any rate, an important idea here is that our inductive arguments about the future suppose that things in the future will behave like they did in the past. We then ask, how can we know this? The next point seems to be that we cannot say that we know this with the following reasoning: in the past, there was always a high probability that the future is consistent with the past. I am not certain, but the problem here might be that we are trying to justify inductive reasoning, but we cannot use inductive reasoning to do so. I am not sure that is it, because suppose we wanted to justify deductive or demonstrable reasoning. Would we have to use some other sort of reasoning to do so? Let me quote so you can see. (I find objections to circularity to be tricky to grasp straightforwardly.)]
If we be, therefore, engaged by arguments to put trust in past experience, and make it the standard of our future judgement, these arguments must be probable only, or such as regard matter of fact and real existence, according to the division above mentioned. But that there is no argument of this kind, must appear, if our explication of that species of reasoning be admitted as solid and satisfactory. We have said that all arguments concerning existence are founded on the relation of cause and effect; that our knowledge of that relation is derived entirely from experience; and that all our experimental conclusions proceed upon the supposition that the future will be conformable to the past. To endeavour, therefore, the proof of this last supposition by probable arguments, or arguments regarding existence, must be evidently going in a circle, and taking that for granted, which is the very point in question.
(online / 26)
4.2.20
[Our inductive reasoning is based on the assumption that like causes will have like effects. But there is no act of deductive reasoning which allows us to make this conclusion. For, if it existed, we would be able to conclude all future cases of some experienced situation will have the same effects. But in fact, we first need a long series of uniform such experiences before we are inclined to draw such a conclusion.]
So, we trust that when causes appear similar, the effects will be similar. [I am not sure, but Hume’s next points might be the following. This is not an a priori notion. For, if it were, then we would for example upon eating an egg for the first time expect all future times to have the same taste and provide the same enjoyment. But in fact we need a long series of uniform events before we have such certainty about future cases. I do not understand the last point; maybe it is something like the following. Let me quote it first: “Now it seems evident that, if this conclusion were formed by reason, it would be as perfect at first, and upon one instance, as after ever so long a course of experience. But the case is far otherwise. Nothing so like as eggs; yet no one, on account of this appearing similarity, expects the same taste and relish in all of them. It is only after a long course of uniform experiments in any kind, that we attain a firm reliance and security with regard to a particular event. Now where is that process of reasoning which, from one instance, draws a conclusion, so different from that which it infers from a hundred instances that are nowise different from that single one? This question I propose as much for the sake of information, as with an intention of raising difficulties. I cannot find, I cannot imagine any such reasoning.” So we began by noting the first experience of eating eggs. We drew from that experience no conclusion about future such experiences of eggs. But to make this particular interpretation work, we need to think that we did draw a conclusion, namely that future instances may or may not be the same. After a hundred such experiences of eating eggs, we come to a different conclusion, which is that all future instances will be similar. (The difference being that the second conclusion has a greater degree of “certainty” that the future cases will resemble the prior ones.) Hume then wonders if there is some process of reasoning that causes us to draw the more determinate conclusion after many experiences. He says he cannot think of any. The point might be that were such reasoning available, we would have been able to draw the conclusion after the first instance. (Instead it seems that some kind of force of association alters our tendencies to draw inductive conclusions.)]
In reality, all arguments from experience are founded on the similarity which we discover among natural objects, and by which we are induced to expect effects similar to those which we have found to follow from such objects. And though none but a fool or madman will ever pretend to dispute the authority of experience, or to reject that great guide of human life, it may surely be allowed a philosopher to have so much curiosity at least as to examine the principle of human nature, which gives this mighty authority to experience, and makes us draw advantage from that similarity which nature has placed among different objects. From causes which appear similar we expect similar effects. This is the sum of all our experimental conclusions. Now it seems evident that, if this conclusion were formed by reason, it would be as perfect at first, and upon one instance, as after ever so long a course of experience. But the case is far otherwise. Nothing so like as eggs; yet no one, on account of this appearing similarity, expects the same taste and relish in all of them. It is only after a long course of uniform experiments in any kind, that we attain a firm reliance and security with regard to a particular event. Now where is that process of reasoning which, from one instance, draws a conclusion, so different from that which it infers from a hundred instances that are nowise different from that single one? This question I propose as much for the sake of information, as with an intention of raising difficulties. I cannot find, I cannot imagine any such reasoning. But I keep my mind still open to instruction, if any one will vouchsafe to bestow it on me.
(online / 26)
4.2.21
[How can we be sure that like causes will have like effects and thus that the future will resemble the past? We cannot. We can only trust inductive conclusions for practical reasons. But there is no reasoning that will take us from the premises to the inductive conclusion.]
If we just say that we infer the inductive conclusion, then we still need to explain [what interposing ideas allow us to move from premises to conclusion, as there is no necessary connection between them.] This inference is neither intuitive [as it not immediately apparent but only so after much repetition, perhaps] and it is not demonstrative [as it does not follow by necessity from the premises]. But of what nature is this inference that the future will resemble the past? [It is not enough to say that it is based on experience, because nothing prevents us from experiencing something different in the future.] [And again, we cannot say that inductive inference is reliable by pointing to its reliability in the past, because we are using the same point to conclude the same point, namely, that a uniformity of outcome is enough to predict future uniform outcomes.] [I do not follow the next points well. Maybe they are the following. Hume has us assume that all events up to now have been uniform. Nonetheless, on that basis alone, we cannot conclude they will remain uniform in the future. Hume says that the causal properties of objects might change. (He even says this happens sometimes for some objects, but he does not give more specifics.) Hume then notes that we cannot be protected from this possibility. Perhaps we might reply that our experiences are so consistent that they are worthy of trust. Hume it seems is acknowledging that for practical purposes we can have this trust. (So for example we can set our clocks at night expecting the sun will rise tomorrow.) But as philosophers, we demand more than a practical justification for certainty in our knowledge. (If really there are grounds to draw these inferences, rather than mere practical conveniences for doings so, we can still as philosophers demand to know what they are. To think of this another way, science, which uses this sort of inductive reasoning about the future to make predictions, can claim that for all practical purposes we can expect things to be the same in the future. We see this sort of defense from Richard Dawkins when he says, “It works, bitches” when facing the same philosophical challenge to inductive knowledge. But this means that science cannot make claims of truth. We cannot say these inferences are “true” but only that for practical purposes we will trust them.)]
Should it be said that, from a number of uniform experiments, we infer a connexion between the sensible qualities and the secret powers; this, I must confess, seems the same difficulty, couched in different terms. The question still recurs, on what process of argument this inference is founded? Where is the medium, the interposing ideas, which join propositions so very wide of each other? It is confessed that the colour, consistence, and other sensible qualities of bread appear not, of themselves, to have any connexion with the secret powers of nourishment and support. For otherwise we could infer these secret powers from the first appearance of these sensible qualities, without the aid of experience; contrary to the sentiment of all philosophers, and contrary to plain matter of fact. Here, then, is our natural state of ignorance with regard to the powers and influence of all objects. How is this remedied by experience? It only shows us a number of uniform effects, resulting from certain objects, and teaches us that those particular objects, at that particular time, were endowed with such powers and forces. When a new object, endowed with similar sensible qualities, is produced, we expect similar powers and forces, and look for a like effect. From a body of like colour and consistence with bread we expect like nourishment and support. But this surely is a step or progress of the mind, which wants to be explained. When a man says, I have found, in all past instances, such sensible qualities conjoined with such secret powers: And when he says, Similar sensible qualities will always be conjoined with similar secret powers, he is not guilty of a tautology, nor are these propositions in any respect the same. You say that the one proposition is an inference from the other. But you must confess that the inference is not intuitive; neither is it demonstrative: Of what nature is it, then? To say it is experimental, is begging the question. For all inferences from experience suppose, as their foundation, that the future will resemble the past, and that similar powers will be conjoined with similar sensible qualities. If there be any suspicion that the course of nature may change, and that the past may be no rule for the future, all experience becomes useless, and can give rise to no inference or conclusion. It is impossible, therefore, that any arguments from experience can prove this resemblance of the past to the future; since all these arguments are founded on the supposition of that resemblance. Let the course of things be allowed hitherto ever so regular; that alone, without some new argument or inference, proves not that, for the future, it will continue so. In vain do you pretend to | have learned the nature of bodies from your past experience. Their secret nature, and consequently all their effects and influence, may change, without any change in their sensible qualities. This happens sometimes, and with regard to some objects: Why may it not happen always, and with regard to all objects? What logic, what process of argument secures you against this supposition? My practice, you say, refutes my doubts. But you mistake the purport of my question. As an agent, I am quite satisfied in the point; but as a philosopher, who has some share of curiosity, I will not say scepticism, I want to learn the foundation of this inference. No reading, no enquiry has yet been able to remove my difficulty, or give me satisfaction in a matter of such importance. Can I do better than propose the difficulty to the public, even though, perhaps, I have small hopes of obtaining a solution? We shall at least, by this means, be sensible of our ignorance, if we do not augment our knowledge.
(online / 27-28)
4.2.22
[It could be that the rational justification for inductive inference exists but that we have not found it yet.]
[Hume then acknowledges that he might have simply failed to find the rational justification for inductive conclusions. He also notes that just because no one in the past has provided this reasoning, we cannot conclude that none exists. However, Hume still thinks we can be more or less sure of this in this case.]
I must confess that a man is guilty of unpardonable arrogance who concludes, because an argument has escaped his own investigation, that therefore it does not really exist. I must also confess that, though all the learned, for several ages, should have employed themselves in fruitless search upon any subject, it may still, perhaps, be rash to conclude positively that the subject must, therefore, pass all human comprehension. Even though we examine all the sources of our knowledge, and conclude them unfit for such a subject, there may still remain a suspicion, that the enumeration is not complete, or the examination not accurate. But with regard to the present subject, there are some considerations which seem to remove all this accusation of arrogance or suspicion of mistake.
(online / 28)
4.2.23
[We can be sure that is no rational justification for inductive inferences, because creatures incapable of rational thinking (like infants and animals) have no problems drawing such inductive inferences.]
[We can know that there is no logical reasoning behind inductive inference, because creatures that have no capacity for reasoning still draw these “inferences”. Children, for example, learn from pain, like learning to keep their hands away from candles after once burning their hands on a candle flame. Hume then goes through possible responses. If we say the child draws this conclusion from some sort of argumentational or logical thinking, then we need to state that reasoning. Presumably we cannot produce it, perhaps because there is no such logical reasoning that we would ascribe to an infant (who has yet to learn language or how to correctly draw logical inferences). We also may not say that the argument cannot be given on account of it being very complicated or difficult, because then an infant would be incapable of conceiving it. The next response might be the following, but I am unsure. Suppose that we take a long while to produce the reasoning that the child used. This shows that we are wrong, perhaps because the child draws the inference instantly and not after much reflection. Hume says that if he is right that inductive inference is not rationally justifiable, than he has not made a great discovery. Perhaps this is his characteristic modesty, here based on the idea that he has only proved a negative and not discovered something positive. He then very cleverly says, “if I be wrong, I must acknowledge myself to be indeed a very backward scholar; since I cannot now discover an argument which, it seems, was perfectly familiar to me long before I was out of my cradle.” He is saying that probably his is right about this, because were he wrong, then he should be able to know something that was obvious to him since the time he was infant.]
It is certain that the most ignorant and stupid peasants—nay infants, nay even brute beasts—improve by experience, and learn the qualities of natural objects, by observing the effects which result from them. When a child has felt the sensation of pain from touching the flame of a candle, he will be careful not to put his hand near any candle; but will expect a similar effect from a cause which is similar in its sensible qualities and appearance. If you assert, therefore, that the understanding of the child is led into this conclusion by any process of argument or ratiocination, I may justly require you to produce that argument; nor have you any pretence to refuse so equitable a demand. You cannot say that the argument is abstruse, and may possibly escape your enquiry; since you confess that it is obvious to the capacity of | a mere infant. If you hesitate, therefore, a moment, or if, after reflection, you produce any intricate or profound argument, you, in a manner, give up the question, and confess that it is not reasoning which engages us to suppose the past resembling the future, and to expect similar effects from causes which are, to appearance, similar. This is the proposition which I intended to enforce in the present section. If I be right, I pretend not to have made any mighty discovery. And if I be wrong, I must acknowledge myself to be indeed a very backward scholar; since I cannot now discover an argument which, it seems, was perfectly familiar to me long before I was out of my cradle.
(online / 28-29)
From:
Hume, David. 2007. An Enquiry concerning Human Nature. Peter Millican (ed.). Oxford: Oxford University.
Text available online at:
http://www.gutenberg.org/ebooks/9662
PDF available at:
https://archive.org/details/enquiryconcernin00humeuoft
Or if otherwise noted:
Peter Millican. “Introduction.” In [see above].
Peter Millican. “Explanatory Notes.” In [see above].
.
No comments:
Post a Comment