This is cassette 10, concerned with Ockham's theory of knowledge, in particular with his rejection of the "species" theory of knowledge, and with his views on intuitive knowledge. In rejecting species Ockham agreed with Henry of Ghent, with whom he often disagreed.
First some background on the "species" theory. On all of this see Katherine Tachau, Vision and Certitude in the Age of Ockham. "Species" in this context means form, not species in the sense in which species are the subdivisions of a genus. According to the usual medieval account, when we see an object it is because its species have been transmitted through the transparent medium (say, the intervening air or glass or water) and have impinged upon our eye. Then, they said, the species received in the eye has been transmitted further through the optic nerve into the brain and there received into the soul, where the agent intellect disengages the species from its material carrier and expresses (makes explicit) an intellectual species, which is received into the passive intellect and understood. See PHIL252 Readings, pp.153-4. This theory is not so very unlike modern ideas of perception. Instead of species passing through the air we think of light rays, instead of species passing through the optic nerve we think of a chemical and/or electrical impulse or chain reaction. The medieval theory did not mean that little forms fly off the object and fly through the air, as the ancient atomist Democritus had held that streams of atoms pass from the object to the eye. Rather in medieval Aristotelian theories the object acts on the immediately adjacent part of the medium and changes it, and that change produces a similar change in the next part of the medium, and so on to the eye, and there the change produced in the eye by the change in the last part of the medium produces a change in the first part of the optic nerve and so on. They thought of it as a chain reaction like the burning of a fuse. The species is transmitted by being reproduced successively through the medium. The effect of the object's physical powers on the medium resembles the object in the sense that eventually the soul can correctly decode what it receives, but what passes through the medium is a modification of the medium, having characteristics due to the medium (say air) as well as characteristics due to the object. A transparent medium is one in which the characteristics due to the medium do not prevent the soul from correctly abstracting from what it receives the species of the object.
When Isaac Newton proposed his theory of gravity--that all bodies in the universe attract one another with a force inversely proportioned to the square of their distance and proportional to the product of their mass--it was objected by his contemporaries that he was postulating action at a distance, because no medium could be assigned through which this force could be propagated. Some postulated "ether" as an otherwise unknown medium for the propagation of the force of gravitation and electro-magnetic waves, thus avoiding the hypothesis of action at a distance. In rejecting species Ockham does postulate action at a distance. The knower knows the object across a distance with no linking medium. See Adams, William Ockham, pp.830-834 for Ockham's discussion of attempts to explain by the "species in the medium" theory some of the more difficult cases. For example Ockham asks us to imagine sunlight streaming into a room through an open window and illuminating part of the floor. On the species theory the air just outside the window would be changed by a chain reaction going back to the sun, and that air just outside the window would cause a change in the air just inside the window, and so on down to the floor. But, Ockham asks, why does this chain reaction act only in a straight line with the sun? If the air just inside the window passes an effect down towards the floor, why not also in all the other directions so as to illuminate the whole room?
Another case, the iron attracted by a magnet: Species theorists postulated transmission from the magnet of a change which induces in the iron a new form analogous to mass which causes it to move, not downwards like mass, but toward the magnet. Ockham asks: why in that direction? Would it not be simpler to suppose that the magnet moves the iron toward it from a distance?
So Ockham holds that there are no species, nothing passes through the medium from object to knower. This was a pretty drastic departure from the current theories. Ockham's contemporaries and successors generally rejected it, not out of hand, but because they did not think he could account for all the phenomena without species. Early modern philosophers and scientists in Newton's time held some version of the theory that species are transmitted through the medium and that bodies cannot act on one another from a distance without a medium.
This brings us to the second question. The editors of the recent edition of Ockham refer us to Thomas Aquinas's Summa theologiae, I, q.55, arts.1-3. Read the three paragraphs under the next heading, "The opinion of St. Thomas on the second question". Notice in the third paragraph Ockham's razor: the principle that plurality should not be posited without necessity. In the next sentence "everything which is preserved with a species": "preserved here translates salvari, which is generally translated "save", as in the phrase "saving the phenomena", or "saving the rights of other interested parties" etc. To "save" the phenomena (phenomena meaning appearances) is to construct your theory in such a way that every appearance or observation is adequately accounted for, with nothing overlooked--i.e., the theory accommodates all the empirical data. So Ockham is saying that all the phenomena of knowledge can be as well explained without species as with them, so species are not needed, and by the razor principle should therefore not be posited.
Intuitive cognition corresponds to basic observations in modern empiricist theories. Intuition enables me to judge evidently, without any process of inference, that S is, or that P is, or that S is P. At the end of the paragraph he refers to self-evident abstract principles, e.g. that the whole is greater than any of its parts. We can judge evidently, without nay inference or proof, that it is true that the whole is greater than the part as soon as we apprehend the meaning of "whole", "greater", "part". Ockham is setting up a parallelism between self-evident abstract principles and basic observations: in both cases we "see" without proof or further argument that the statement is true. "Intuitive" comes from the Latin verb intueri, which means "to see".
However, there is a difference: self-evident abstract (or general) principles are not based directly on intuition (we can judge that every whole is greater than any part whether or not we are now intuiting any whole or parts), but we can't judge evidently that this body is white except by intuition of the body and its whiteness. Self-evident general prepositions can be known through abstractive cognitive, but evident particular propositions are known only through intuitive cognition.
Ockham followed Scotus in distinguishing between intuition and abstractive cognition and in holding that both the senses and the intellect have intuitive cognition (On Scotus see Hyman and Walsh, p.590). When I look at Socrates I see him literally with my eye, and I also "see" him with my intellect. According to Ockham sense intuition is normally in this life needed before we can have an intellectual intuition, and sense intuition somehow causes the intellectual intuition to occur, perhaps by triggering action by the intellect. The immediate causes of my intellectual intuition of Socrates are (normally) Socrates (acting at a distance) and my intellect. (See Adams, William Ockham, pp.507-9). Scotus and Ockham do not limit the human intellect to what can be sensed, as Thomas Aquinas does. Remember that according to Scotus the first object of our intellect is being in general, not only material being; but for some reason, perhaps as a result of Adam's sin, our intellect in this life cannot directly know immaterial substances (cf. Hyman and Walsh, p580). Similarly Ockham holds that in this life we need sense intuition before we can have intellectual intuition, but sensation is not one of the immediate causes of intellectual intuition. (This is a Platonic and Augustinian element in Ockham's thinking. Compare Plato's doctrine of reminiscence.)
At the beginning of the next paragraph, "But it should be known", insert a left hand bracket; insert a right hand bracket on p.628, line 11, after "as well as presence". At this point a new paragraph should begin--all of that is a clarifying digression that a modern author might put into a footnote. On p.627, seven lines up from the bottom, for "were to divide" substitute "divide". Ockham leaves the question open. In the last two lines on this page before "abstractive" insert "the" and delete the comma before cognition, change "which" to "that" (this is a defining relative clause). On p.628, line 9, for "it is not intuitive cognition" etc. substitute "intuitive congition, whether sensitive or intellective, is not a partial cause". Read the paragraph in brackets.
What Ockham is saying here is that by the intuition he means the cognition of the body and of the whiteness, not the apprehension of the proposition "the body is white" or of its meaning. We can contemplate and understand the proposition with or without intuiting any white body. Intuition is what enables us not merely to consider and understand but to affirm with certainty that the body is white. Through intuition we can affirm a proposition that we can form or understand or consider without intuition.
In the next section, "So, therefore", change "exists" to "be", which covers both "exists" (as when we say "there is a body" or "there is a white thing") and the "is" that joins subject and predicate, "The body is white". Intuitive cognition is the basis of both kinds of judgment, that something exists and that it has some character. Read down to the middle of the page.
Some more amendments. In the first line of the paragraph that begins "If you say", for "in this way" substitute "here". In line 9 for "which can" substitute "it be able", so that it reads, "no other presence is required... than that it be able to terminate". Three lines further down, for "it exists, if it is in..." substitute "it is, if it is, in...". Three lines further down, before "In the same way", insert a mark, and read down to that mark. Notice in the middle of this section the statement: "it is consistent with this that the object should be nothing", i.e. not exist. He will be more explicit about that possibility later.
Some more amendments to the next section, beginning "in the same way". Five lines down delete "also". Three lines further down delete "And hence, etc. Moreover" and substitute "therefore". In the last line on p.628 change "I see" etc. to "seeing that thing intuitively and having formed this complex" etc. without any semicolon--the force of the "since" carries over to the top of the next page, "the intellect at once asserts". On p.629, line 5, put a full stop after "a pure nothing", and read to that point.
Two things to notice here; first, that we cannot, except by miracle, have an intuitive judgment of non-existence; second, that if God does miraculously cause in us an intuition of a non-existent being, we will know that it does not exist. On the first point: Ockham is not saying that every evident negative particular judgment depends on a miracle. I can look at Socrates and judge evidently that he is not sitting. But I can't judge evidently and directly that he does not exist without a miracle. Where negative judgments are concerned we have to distinguish between "is" in the sense of "exists" and "is" in the sense of "has a characteristic".
Ockham doesn't elaborate, but I think we can see the point. A judgment of non-existence cannot be both evident and direct. Suppose I assert that Socrates does not now exist: this is a certain judgment (perhaps), but it is not direct but inferential. I am inferring his present non-existence from the generalisation that human beings do not live for over 2000 years. This generalisation is perhaps certain to all practical intents and purposes, but perhaps for philosophical intents and purposes we should say that it is extremely probable rather than absolutely certain. So to say that a negative existential judgment cannot be directly evident except by miracle seems fair enough; and accordingly Ockham says that we cannot naturally have an intuitive cognition of a non-existent object.
On the second point, that if God does miraculously cause an intuition of the long-dead Socrates, we will know that Socrates does not exist: otherwise this would not be an intuitive cognition. Remember that this was defined (on p.627, about the middle) as cognition by means of which a thing is known to be when it is and not to be when it is not: the truth of the judgment it causes is part of the definition of intuitive cognition. An intuitive cognition that causes a false judgment is a contradiction in terms. There is more to be said about this, but we will leave it until later.
Some amendments to the next section. On p.629, line 6, for "causation. The case is this:" substitute "causation, an example is:" Four lines down, instead of "for all" substitute "in all respects". The short paragraph near the middle of p.629 should read: "But abstractive cognition is that through which we do not judge that a thing" etc. and in the next line before "whether" insert "and this". In the section we've just read, bottom of 628 to top of p.629, Ockham refers to the causation and conservation of a cognition, i.e. to what brings it first into being, and then what continues it in being; in that section he says that an intuitive cognition can be caused and conserved supernaturally. Now he says that it can be caused naturally but conserved supernaturally. Read to the middle of p.629.
Ockham also discusses the question, What enables me today to remember what I saw yesterday? I couldn't remember it, or have such a cognition in any way, before yesterday, but today and tomorrow I can remember it; so as a result of having it my mind must have acquired a power it didn't have before, which in Ockham's terminology is a habit. But the usual rule with a habit is that it is formed by acts of the same sort as the acts it facilitates; how can the intuitive cognition yesterday have formed a habit by which today I have an abstractive cognition? Ockham is tempted to postulate that every time I have an intuitive cognition I also simultaneously have an abstractive cognition, which generates the habit. But there are objections to this hypothesis. No-one experiences a simultaneous abstractive cognition. So perhaps the habit that makes possible future recollection is generated somehow from the intuitive cognition.
For future reference number the three ways. The term "reason" here translates the Latin ratio, which has a broad meaning, covering reason, cause, conception or notion, and other things. What all the senses distinguished here have in common is that they apply to something previous to the intellectual act that helps to cause it--either all that is previous, or to all but the possible intellect, or to all but possible and agent intellects. The point of these distinctions will emerge later.
Some comments. The argument against species is that there is no reason to posit them--not experience, no argument from higher principles. Look at the passage beginning on the second last line of p.629. "Assumption" means minor premise--in this case that neither experience nor argument from self-evident principles establishes the existence of species. Experience, he says, includes intuition, just as in modern philosophy empirical evidence is often said to include basic observation statements. We do not observe any species, only objects. If you say that the species impressed on the eye, or on the brain, or on the soul, are not the sort of thing that could be seen, Ockham answers that intuitive knowledge is not confined to seeing. We do not intuit species in any way.
As for argument from higher principles, the only relevant principle is the principle of causality, that from effect we can infer cause. However, Ockham says, we cannot infer a cause we never experience in connection with the supposed effect, and species are never experienced. Note here (i.e. p.630, lines 16-18) the anticipation of Hume's doctrine that we can never know something only as an unobserved cause; see Hume's Inquiry Concerning Human Understanding, section IV.
To sum up, then, the fact that we do not experience species is decisive, since it renders inapplicable the only self-evident principle that could be used to prove the existence of species, namely the principle that from the presence of the effect we can infer the activity of the cause. So the first conclusion is that species are not required for intuitive cognition. What about for abstractive cognition?
The experience behind this argument is that we cannot have abstractive knowledge of something unless we have already had intuitive knowledge of the thing or of a thing of that sort. Compare the doctrine of Locke and Hume that we cannot have ideas of something we have never sensed--e.g. we cannot imagine what a pineapple tastes like unless we have already tasted one. See again Hume's Inquiry, section 2; Hume's distinction between ideas and impressions corresponds to Ockham's distinction between abstractive and intuitive sense cognition.
A few amendments to the next section. On p.631, line 10, between "there" and "and if" put a full stop. In the next line, before "And yet", change the full stop to a comma. Two thirds through p.631 "more assimilated to the object in its own nature" should read : "more assimilated in its own nature to an object which is a substance". On p.632, line 13, change "if" to "just as"--"Or, just as you hold". In the middle of p.631, underline the words "assimilation", "causation", "representation", "determination" and "union", and underline the same words as they occur near the beginnings of the paragraphs following on pp.631-2. Read now to the heading "To the first question", two thirds through p.632.
Some comments. "The third conclusion is that what is left"--i.e. the "something" mentioned in the second last sentence of the paragraph before.
In the third paragraph of this section, beginning "Again, when something is in an accidental power", the contrast between accidental and essential power needs explaining. The essential power is what a thing of some kind has essentially, as, e.g., a human being has the power of reason. An accidental power is some additional acquired power; e.g. in a human being the power to understand a particular language, say Italian. The translator's phrase "is in the accidental power" is equivalent to "has an accidental power".
In the next paragraph, beginning, "Again, everything which can be preserved", the "preserved" is Latin salva, usually translated "saved"; I explained earlier what this means. Whatever psychological phenomena can be explained in terms of species can be explained in terms of habit. "But it is obvious" should not be a new paragraph: it continues the argument. Whatever species can explain habit can explain, so so far it doesn't matter which we adopt; but there are some things that habit only can explain, not species; so let's postulate habit to explain those, and it will also explain the others, which species could also explain. What can only habit explain? The fact that the accidental power to know this or that particular thing once we have it is only strengthened by use. The sentence "For a habit is not posited and the species is corrupted" presupposes the hypothesis of the argument--"For were it not required, and a species should suffice", a few lines earlier.
"If you say that the species is strengthened", species and habit theories will again be on a par. The reply that everyone posits habits is weak--perhaps everyone should abandon habits and postulate only species. The previous argument "Again, when something is in accidental power", seems stronger.
The argument beginning in the middle of p.631, with "Again, the species is only posited because of assimilation" etc. continues for the rest of this section. First it is stated complete, then the minor premiss is proved, at "but it is not necessary to posit it because of any of these". The proof is by taking up each of them and showing that species is not needed for that--first assimilation, then representation. The "above" three lines down in the paragraph on representation refers to the first conclusion, p.629.
In the argument beginning two lines from the bottom of p.631 Ockham is saying that we don't have to postulate anything in the mind to represent the object; rather, we know the object directly. If we did postulate a likeness in the mind as a necessary medium representing the object, then we could never get knowledge of the object (cf. Hume)--a representation can't give knowledge of something never known directly.
Hume, like Locke, did postulate a representative medium coming between us and the object, and then showed that this leads to scepticism about the object. See Hume's Inquiry, section 12: Philosophy "teaches us that nothing can ever be present to the mind but an image or perception, and that the senses are only inlets, through which these images are conveyed, without being able to produce any immediate intercourse between the mind and the object". This is the species theory, which Ockham rejects (according to Ockham there is immediate intercourse between mind and object, at a distance). Hume asks,
By what argument can it be proved that the perceptions of the mind must be caused by external objects entirely different from them, though resembling them (if that be possible) and could not arise either from the energy of the mind itself, or from the suggestion of some invisible and unknown spirit, or from some other cause still more unknown to us?... It is a question of fact whether the perceptions of the senses be produced by external objects, resembling them: how shall this question be determined? By experience, surely... But here experience is, and must be entirely silent. The mind has never anything present to it but the perceptions [species], and cannot possibly reach any experience of their connexion with objects. The supposition of such a connexion is, therefore, without any foundation in reasoning.Hume says: We must postulate species, and then we can't avoid doubting the reality of the object. Ockham never doubts the reality of the object, and rejects the species.
On p.632 the next paragraph, "Nor ought a species be posited because of the causation" etc. needs a comment. Ockham holds what he says at the end of this paragraph, that what is corporeal can be a partial cause of a spiritual act. When he says three lines into the paragraph "But against this: Just as what is corporal... cannot be an immediate and partial cause" etc. he is arguing "according to them", i.e. Scotus, who held (following Augustine, who followed Plato, and was later followed by Descartes and Leibniz) that the material cannot act on a spiritual substance: Ockham does not hold this. And he points out here that postulating a species does not resolve the problem that the Augustinian principle generates, because the species is something spiritual, so how can it be produced by a corporal object? The rest of this section should be clear enough.
Here "reason for knowing" is taken in the third of the senses distinguished on p.629, "concerning the reason for knowing". In other words, apart from the intellectual power itself (including the agent and possible intellects), all that is needed for natural intuitive cognition is the object itself.
In the last line of the page, after "knowing" insert a comma, and read to the end of the page. This is clear enough. He is saying that if you want to talk about angels' knowing through species that's alright provided "species" is redefined to mean things known. Similarly in discussing God's ideas through which God was supposed to know his creatures Ockham comes to the conclusion that the divine ideas are the creatures themselves.
Notice in the paragraph "Again" that Ockham rejects the view that the intellect knows only the universal, not the singular. In the omitted part of this paragraph he says, "Thus I say that the intellect knows intuitively the singular as here and now and according to all the conditions according to which the sense knows it, and even according to more". This is a point on which he disagrees with Thomas Aquinas and most other medieval thinkers, who held that we cannot know particular individuals except through a link provided by the senses, as when we say "this", pointing, "is a so-and-so" and then ascribe to this all the characteristics we know belong to so-and-sos.
Some comments. Ockham is answering Scotus, but Thomas Aquinas said something similar. See PHIL252 Readings, p.155. In line 7, "as was said above" refers to a section omitted, in which Ockham discusses memory and imperfect intuitive knowledge: this is the theory that an intuitive cognition is accompanied by an abstractive cognition, which forms a habit enabling future abstractive cognitions of that particular thing, i.e. memories.
In the next paragraph, the two representable characteristics (rationes) are Scotus's nature and individuating thisness. The rest is clear enough.
So what emerges from all of this is that Ockham does not think that there is any reason to postulate an intermediary between the knower and the object. The only causes needed to produce knowledge are the object, which acts on the knower from a distance without anything in the medium (a transparent medium is simply the absence of any intervening obstruction), and the intellect: given an object acting on the knower and the intellect the act of knowledge follows.
A comment: the distinction between complex and incomplex knowledge in this context means the distinction between
Now read Quodlibetal Questions pp.413-7. One minor comment on the translation. On p.416, line 11, for "act of faith" substitute "creditative act"--he does not mean faith in the religious sense, but a pseudo-act of knowledge to which we give credence. The meaning of these few pages in pretty clear.
Note that what prevents a deceptive intuition is simply the definition of the term "intuition", which includes "evident", which connotes that the proposition believed is true. But this does not prevent a deception that we mistake for an intuition. A definition can never prevent something from happening, though it may prevent the happening from being described in a certain way. Notice the last paragraph of the reply to objection 1, and the end of the first paragraph of the reply to objection 4, "Nonetheless, I grant... ": We can have what we think is an intuition by which we are deceived. Similarly in ancient times the Sceptics emphasised that there is no mark or criterion by which we can distinguish between false and veridical perceptions or seeming perceptions.
Now read Quodlibetal Questions pp.506-8. This is clear enough. It explains in more detail the reasoning behind a doctrine we have seen in all the passages we've read on intuitive cognition, namely that while naturally intuitive cognition requires the existence and presence of its object, it is possible for such a cognition to be caused miraculously by God. This passage does not comment on the question whether if we had a miraculous intuition we would know that the object does not exist, but presumably he holds to what he has said in several other places, that we would know that the object does not exist, otherwise the cognition would not qualify as intuitive (since it would be false). But as we saw in the previous passage, God can cause visions by which we are deceived. This possibility has led some to say that Ockham is a sceptic, or would have been if he had followed his argument right through. See E. Gilson, The Unity of Philosophical Experience, pp.61-91, and Adams William Ockham, chapter **. On the other topic of this lecture, the rejection of species, see Tachau Ch.5 for Ockham's views, and ch.6, especially pp.174-9, 198-202, for the rejection of Ockham's views by his contempories and successors.
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