Coffey: Primary and Secondary Qualities #4

Philosophers have characterized the difference between primary and secondary qualities in various ways.

1. On 9/22 I quoted Coffey's distinction between qualities in actu (perceived) and in potentia  (unperceived) respecting the secondary qualities sweetness, whiteness, etc. He doesn't make and says there is no ground for the same distinction between primary qualities, e.g. roundness, size, etc. (Vol. 2, p. 128-9). Maybe that is because he couldn't conceive of any sort of dissimilarity between such primary qualities perceived and unperceived, and his saying so would have been an indirect agreement with John Locke. Locke: "From whence I think it is easy to draw this observation, that the ideas of primary qualities are resemblances of them, and their  patterns do really exist in the bodies themselves; but the ideas produced in us by these secondary qualities have no resemblance of them" (ECHU, II, VIII, 15). An example of the latter is perceived color versus light wave frequency.

2. Another way of stating the difference is that primary qualities are categorical but secondary qualities are dispositional.  In this context "dispositional" means a quality that is manifested given the appropriate circumstances. Analogous examples: (a) glass is fragile in that it will break if struck hard enough, and (b) sugar or salt is soluble in that it dissolves in water.

3. Another way of stating the difference is primary qualities are intrinsic but secondary qualities are extrinsic or relational.

Coffey: Primary and Secondary Qualities #3

Thomas Case's book Physical Realism was published in 1888. Coffey used it to present and criticize its view of primary and secondary qualities.

Physical realism is the view that sense qualities are neither conscious states nor modes of the external universe, but modes or states of the perceiver's organism. It is favored by many scientists. Since nothing external can be immediately apprehended, but only inferred (by the principle of similarity) from data that are internal, we can ascertain the real nature of these latter data only by asking ourselves from what kind of data can we have inferred the objects which science assures us to be externally real. Such data must be internal but also physical, i.e. of the same order as the objects inferred by science. They cannot be purely psychic states. But the only objects which science assures us to be externally real are extension, volume, shape, motion, etc., which are like their internal sensible correlates, and such transcendentally inferred imperceptible modes of the former as e.g. corpuscles, undulations of aether, etc.: that correspond externally to the internal secondary qualities. And the reason why the former externals are like their internal correlates, and the latter unlike theirs, must be because the perceiver's sense organon is so constituted that it is capable of assuming in itself, and presenting to consciousness, states similar to the primary externals under the influence of the latter, whereas it can assume and present to consciousness under the influence of the secondary externals only states dissimilar to these.  (Vol. 2, p.124-5).

Coffey sees no sufficient grounds for this view, for example, external motion is like sensible motion, but external heat is an imperceptible mode of motion while sensible heat is not sensibly a motion at all. He objects to the motion example considering the motion of a train or hailstorm saying that the internal, sensible appearance is an immediately apprehended nerve motion or organic condition appearing as an external train or hailstorm motion.  (I don't buy his argument there when I consider the co-occurring retinal image.)  (Vol. 2, p.126-7).

A little later, he expresses his objection as follows: "For since the whole sense organon is an extramental material factor, we cannot say that it presents to conscious one set of qualities as they are--whether in itself or in the extra-organic domain, or partly in the one and partly in the other, but in both cases--beyond or independently of consciousness, and another set otherwise than they are beyond or independently of consciousness" (Vol. 2, p.133).

Coffey: Primary and Secondary Qualities #2

Coffey's view is that there is no difference knowledge-wise between primary and secondary qualities. Of course, he doesn't argue against the distinction Aristotle made between the common and proper sensibles -- those that are perceived by more than one sense (shape, mass, motion, solidity, number) and those that are perceived by only one sense (color, taste, sound, smell). He disagrees with and critiques two alternative views -- immaterialism and physical realism.

Coffey devotes several pages to the view of Bishop George Berkeley. Since Coffey criticized immaterialism rather than primary and secondary qualities, I will be brief.

In Berkeley's book Three Dialogues between Hylas and Philonous,  Berkeley's views were represented by Philonous (Greek: "lover of mind"), while Hylas (Greek: "matter") embodies Berkeley's opponents, in particular John Locke. Hylas presents the primary-quality distinction as follows.

"You must know sensible qualities are by philosopher divided into primary and secondary. The former are extension, figure, solidity, gravity, motion, and rest. And these they hold really existing in bodies. The latter are those above enumerated [colors, sounds, tastes, etc.]; or briefly, all sensible qualities beside the primary, which they assert are only so many sensations or ideas existing nowhere but in the mind" (Three Dialogues). 

Locke wrote: "Such qualities, which in truth are nothing in the objects themselves but powers to produce various sensations in us by their primary qualities, i.e. by the bulk, figure, texture, and motion of their sensible parts, as colours, sounds, tastes, &c., these I call secondary qualities" (An Essay Concerning Human Understanding, Bk. II, Chap. 8, Sect. 10).

Thus Berkeley misrepresented Locke's claim. Primary qualities cause the perceived secondary qualities.

Coffey: Primary and Secondary Qualities #1

Coffey wrote much about primary qualities (or common sensibles) versus secondary qualities (or proper sensibles) in Epistemology; Or the Theory of Knowledge. He presents the scholastic view of secondary qualities with which he agrees as follows.

"The names of the various proper and secondary sense qualities,--of colors, sounds, tastes, smells, tactual and temperature qualities,--are not names of mental states, or of organic states, conditions or qualities, of the perceiver: they are names of qualities of external or extra-orgaanic bodies. But Aristotle, St. Thomas, and the scholastics generally, while holding that these qualities are really in external bodies independently of our actual perceptions of them, realized the necessity of distinguishing between the unperceived reality of these qualities, and the characters which their reality assumes in our actual perception of them: between those qualities in actu and in potentia. In the untasted sugar there is real sweetness but not the sensation or perception or taste of sweetness; in the unseen snow there is real whiteness but not the vision of whiteness, or actually perceived whiteness; in the unheard tempest there is real sound, but not the hearing or actual sensation or perception of sound; in the unsmelt violet there is real perfume but not the actual smell or perception of the perfume; and so on. In other words, if we understand the name of the sense quality to denote this quality as actually perceived,  and thereby to connote as part of its meaning the actual conscious perception process or state itself, then of course the quality so named cannot be in the unperceived external domain actually (in as much as the sensation or perception process is absent from the unperceived domain); but nevertheless the unperceived quality is really there, and we can say it is there potentially or virtually, meaning thereby, not that the quality is any less really these when unperceived than when perceived, but that as unperceived it is a potential or virtual percept or term of a conscious perceptive process; in other words that it is a reality capable of being perceived though not actually perceived" (Vol. 2, p. 106-7).

Coffey: Senses and Intellect #3

More from Peter Coffey's Epistemology; Or the Theory of Knowledge follows. Coffey presents the scholastic theory of necessary judgments that he advocates.

"When, therefore, I reflect on my spontaneous assent to such a judgment as that 7 + 5 = 12, I observe the following facts: (a) that I affirm a necessary identity between predicate and subject; (b) that I affirm the identity after having seen it intellectually through comparison of the concept of "12" with the concept of  "7 + 5"; (c) that I affirm it because I have seen it. Moreover, I observe that (d) I see the necessary identity because I see that the concepts necessarily involve such identity [ ]" (Vol. 1, 234).

"How are the absolute necessity and universality of these relations to be accounted for? Manifestly these characteristics cannot appertain to any objects as perceived through sense experience, for they transcend the limits of sense experience. The necessity and universality in question are not empirical or a posteriori. They characterize objects not as perceived by sense but as conceived by intellect. The questions is, why or how is it that objects, as conceived, reveal such relations?
   "The answer is that the objects reveal those relations because intellect, in conceiving them, apprehends them in the abstract, i.e. divested of all the conditions of the contingent, actual, physical existence whereby alone they can be data or objects of sense experience. It apprehends them (in their essence or nature) as being independent of the limitations under which, in their sensible, physical, material existence, they come into sense experience: and because it so apprehends them it can and does see in them properties, laws, relations, which characterize their essences, their actual physical existence must necessarily and universally conform. And it is our intellectual intuition of these objects as involving such properties, laws, and relations, that gives us the absolutely necessary and universal judgment,--the judgment which is a priori in the sense that it is not grounded in sense experience [ ]" (Vol. 1, 241-2).

   "The abstractive and intuitive character of intellectual conception or thought is thus the key to the characters of necessity and universality in judgment of the ideal order. The intellect abstracts, as its proper objects, from the concrete, individual data or conscious sensation and reflection, the reality which constitutes the essences or nature of these data: these essences or natures it contemplates in this condition of abstraction in which they are static, changeless, self-identical entities: and thus it sees them to be characterized by properties and relations which, like themselves, are immutable necessary, eternal, etc." (Vol. 1, 243).

I believe there is merit in his making a sharp difference between sense and intellect, but it seems to me too sharp. I see conflict between the first and second excerpts. In the first he asserts the identity of  7 + 5 = 12 after having seen it, though intellectually. Yet in the second he asserts the judgment is not grounded in sense experience. How anyone could see that 7 + 5 = 12 is true intellectually without seeing it grounded in sense experience is incomprehensible to me. Indeed, such a claim is very much like Kant's, with which Coffey had earlier strongly disagreed.

Coffey: Senses and Intellect #2

 As noted in my prior post, Peter Coffey mentioned the straight stick partly submerged in water on page 237 of Volume 1 of Epistemology; Or the Theory of Knowledge. He addresses said stick again in Volume 2 as follows.

"But the presentation of a sense datum can be an occasion of deception to the perceiver, inasmuch as the latter may judge that the datum is external, or how it is externally, without adverting to the fact that the presented datum is partially determined by the conditions of his organism, and this condition is, perhaps, abnormal. And just as the subjective, organic condition of the perceiver may be an occasion of error in his spontaneous judgment, so may the abnormal condition of the external thing itself, or the physical medium spatially intervening between the latter and the sense organ of the perceiver. A trite and telling example of this source of error is the familiar fact that a straight stick partially immerses in water and seen obliquely appears bent. Or again, to a person sitting in a moving train which is passing another train that is stationary, the latter appears to be moving and the former at rest: a double or compound illusion. Or, an object seen through a microscope appears much larger than "it really is". [ ]
   "Now such "illusions of the senses," though puzzling to the plain man, have never shaken his spontaneous belief in the trustworthiness of his senses under normal conditions. But philosophers, who have tried to think out the bearing of these illusions on our spontaneous beliefs regarding the existence, qualities, and nature of the external domain of reality, have been more than puzzled by such illusions: many have been driven by them into the position of theoretical scepticism, subjectivism or idealism" (p. 93-4).

Straight trumps bent because the stick is seen as straight when not in the water or fully immersed in the water, and can be felt as straight even while seen as bent. We judge that under most and normal conditions perception matches reality. However, such analysis does not apply to a circular table top. Under most and normal conditions the table top is seen as elliptical rather than circular, and we judge it to be really circular. On the other hand, we don't regard the elliptical case as an illusion. In every case what is seen conforms to and depends on the retinal image.

These example, the trains, the moon seeming almost as large as the sun, the railroad tracks that seem to converge, and others seem to support no comprehensive rule for identifying illusory versus non-illusory percepts.

Coffey: Senses and Intellect #1

More from Peter Coffey's Epistemology; Or the Theory of Knowledge follows.

"Through the impressions produced on our senses by objects, the latter necessarily make us aware of them as they appear, even when they appear to us as otherwise than they really are. A straight stick, plunged in water, necessarily appears to the eye as bent; two plane pictures, seen through the stereoscope, necessarily appear as one solid object seen in perspective or relief; and so on. We can correct such illusions of course; but it is by intellect we correct them, not by sense: the deceived sense can never correct its own deception. Or rather, we should say, it can never correct the error:  the intellect judging spontaneously that such objects are as they appear.   [ ]
   "But while sense is thus necessitated in revealing to us how things appear, intellect is not necessitated by the mere sense impressions in judging how things are. Our sense-awareness or sense-consciousness of how things appear is not knowledge, it only furnishes the materials of knowledge, the data for interpretation. Knowledge proper is knowledge of how and what things are; it is attained only by judgment; and judgment has its immediate object the assertion of a nexus (of identity or non-identity) as real" (Vol. 1, 237-8).

His using necessarily seemed superfluous to me until he contrasted the senses with the intellect. In my opinion "not necessitated" sounds correct for judgment, but "necessitated" sounds a little off for the senses. Regarding the sense data as "given" and the judgment as "not given" sounds better to me.