Eugene Lashchyk, Scientific Revolutions, 1969

(B) Facts Are Paradigm-Laden

Theses 2: There is no neutral observation language. Every description of phenomena will be in the terminology of some theory, paradigm, current metaphysics, or the world view implicit in ordinary language. For the purposes of science it can be said that what is a scientific fact will be in an important sense determined by the dominant paradigm, for descriptions of some aspect of phenomena must be couched in the language of the current scientific theory. Should this not be possible such an observation of phenomena will appear to be anomalous and will not be a full-fledged scientific fact until the anomaly is removed.{3}

I am basically in agreement with Professor Kuhn on Thesis 2. What I would like to do, however, is to look at some of the things that Professor Kuhn says concerning this thesis, particularly, how such things as observations, descriptions and anomalies, discovery and facts are interrelated. Besides this limited objective, I would also like to make some comments concerning the relevance of Thesis 2 to Thesis 3.

By denying the existence of a pure observation language, which some logical positivists presupposed, Kuhn is repeating a theme that is becoming more and more accepted by the philosophical community.{4}

In criticizing the ideal of a neutral observation language Kuhn states:

. . . attempts to make it do so through the introduction of a neutral language of observations now seem to me hopeless.
The operations and measurements that a scientist undertakes in the laboratory are not 'the given' of experience but rather 'the collected with difficulty.' They are not what the scientist sees -- at least not before his research is well advances and his attention focused . . . . Far more clearly than the immediate experience from which they in part derive, operations and measurements are paradigm-determined. Science does not deal in all possible laboratory manipulations. Instead, it selects those relevant to the juxtaposition of a paradigm with the immediate experience that the paradigm has partially determined.{5}

That "operations and measurements are paradigm determined" is not as surprising a claim as might at first appear. Most students of science find out at an early stage that making measurements is not usually as difficult as interpreting them. Without the paradigm-theory supplying the interpretation of the various parameters measured, such measurements lose most of their scientific significance.

Many of the problems surrounding Thesis 2 are clarified when we look at what Kuhn sags about the various types of discovery. Basically there are two types of discovery: d(1) there is the discovery of x where x is a novel phenomenon which was completely unsuspected and unanticipated by the dominant theory or paradigm; d(2) discovery of an x which was predicted by our theory or paradigm but had as yet been unobserved. It is primarily the description of discovery of novel phenomena d(l), which proves to be most illuminating. Kuhn says:

Discovering a new sort of phenomena is necessarily a complex process which involves recognizing both that some thing is and what it is. Observation and conceptualization, fact and the assimilation of fact to theory, are inseparably linked in the discovery of scientific novelty.{6}

To illustrate the difference between recognizing that so and so is the case and recognizing what it is that is the case, let me summarize the story of the discovery of oxygen.{7}

The phlogiston theory explained that combustion takes place when phlogiston, the principle of inflammability, is released into the air. If combustion takes place in an enclosed surface, then it stops when the air in this enclosed surface becomes saturated with phlogiston. It seems therefore, that when a substance undergoes combustion, since it releases phlogiston into the air, it (the substance) should lose weight. An observation was made by Lavoisier in 1772 that some elements gained weight in combustion. Lavoisier wrote:

About eight days ago I discovered that sulfur in burning, far from losing weight, on the contrary, gains it; it is the same with phosphorus; this increase of weight arises from a prodigious quantity of air that is fixed during combustion and combines with the vapors.
This discovery, which I have established by experiments, that I regard as decisive, has led me to think that what is observed in the combustion of sulfur and phosphorus may well take place in the case of all substances that gain in weight by combustion and calcination.{8}

In commenting on this report Conant states:

We seem to see here the flash of genius that puts forward a bold working hypothesis on a grand scale without much evidence to support it. Yet there is no doubt, as Lavoisier always claimed, that the essential idea in his theory was contained in this note; something was taken from the atmosphere in combustion and calcination. This was exactly opposite be it noted, to the phlogiston doctrine. But what was the something?{9}

It was not until chemists began working with red precipitate of mercury that they were on the right track. This is the only known metal, which, even today, when the oxide of the metal is heated, yields mercury and a gas which we now call oxygen. It is the search for the identity of this gas which I would now like to summarize.

Bayen in 1774 noticed that red precipitate of mercury (HgO) could be made to yield a gas by heating. That aeriform product Bayen identified as fixed air (CO2). In August of 1774, Joseph Priestley repeated the experiment and identified the gas which was collected as nitrous air (N20) primarily because it supported combustion. Priestley reported this result to Lavoisier, who repeated this same experiment, but because his tests were more elaborate Lavoisier said it was atmospheric "air itself entire without alteration . . . even to the point that . . . it comes out more pure."{10} In the meantime, Priestley changed his mind twice. At first, he also called the gas "common air", but after further testing reidentified the gas and called it "dephlogisticated air". This, in the phlogiston theory, meant that this gas was atmospheric air which can support combustion because it was deprived of its complement of phlogiston.

After Priestley published his results, Lavoisier again reexamined the gas in question and finally came to the conclusion that the gas was a separable component of atmospheric air. The discovery of oxygen was complete when it was realized not only that here was a new phenomenon, a new type of x, but more important, when it was realized what this phenomenon was. Lavoisier saw that a new category needed to be created, namely oxygen, which was seen for the first time as an irreducible and distinct species of air. Air was thus, not homogeneous, as everyone had thought. Kuhn, commenting on this story, makes the following observation: "Apparently to discover something one must also be aware of the discovery and know as well what it is that one has discovered."{11}

To be aware of a discovery, to be aware that an x is a new type of x heretofore not known to exist and furthermore that it is an x not anticipated by our theories, one has to be usually well versed in the field of specialization in which the discovery occurs. To realize that one is seeing a new type of phenomenon one must know what are the types of phenomena that are predicted by our theories to exist. But realizing that an x is a new type of x is only part of the problem. This in itself can be called a discovery, but there is another aspect to the first type of discovery -- dl. To put it in Kuhnian terminology, seeing a new type of x different from any that one has seen or even expected to see is to experience a anomaly that is "nature's failure to conform entirely to expectation". But things appear anomalous only when normal science or some other beliefs are in the background. In the above example, without phlogiston theory in the background, Lavoisier might never have noticed the anomaly and thus might never have been on the trail of an important research problem. Without such a background, either everything always will appear as the expected and thus in some sense comprehensible, or everything appears as completely unexpected and thus incomprehensible. The first alternative has as yet not been realized and may never be realized by man. For a further discussion of this problem see Chapter IV.

The second alternative seems to be the normal state of affairs with every baby that comes into the world. But seeing something as anomalous is just the first part of making a discovery. When William Herschel reported that "In the quartile near Zeta Tauri . . . is a curious either nebulous star or perhaps a comet"{12} he did not as yet make the discovery of the planet Uranus. He observed that something appeared anomalous, but to identify further what exactly it was one needed to know how it behaves and whether it behaves in ways characteristic of certain already known objects. This is an example of the second type of discovery -- d2. Here the problem is somewhat different from the oxygen example. In the oxygen case to further identify what the gas was, one needed to make a conceptual revision. One needed to modify one's categories, i. e., those concepts which stand for things that are thought to exist at a particular state of man's knowledge. The discovery of oxygen was thus much more monumental a discovery for it required the reorganization of our basic categories. To put it in Kuhnian terminology, seeing this particular gas as oxygen, rather than dephlogisticated air required a certain gestalt switch which gave rise to a new paradigm. It seems that Kuhn would want to generalize and say that whenever a discovery requires a change in perspective, such discoveries give rise to scientific revolutions. Kuhn states:

Like the work of Herschel and Roentgen, that of Priestley and Lavoisier taught scientists to view old situations in new ways. . . . But, in the case of oxygen, the readjustments demanded by assimilation were so profound that they played an integral and essential role . . . in the gigantic upheaval of chemical theory and practice which has since been known as the "chemical revolution" . . . every such discovery demands . . . the sorts of readjustments that we equate with scientific revolutions.{13}

Change in perspective and change in theoretical framework are thus the two ingredients of a revolutionary period in science.

My original quote above which stated that discovery "involves recognizing both that something is and what it is" can now be more fully explained, for the discovery that an x is a new type of x requires change in perspective.{14} For anyone who doesn't see the x from the new perspective will not see the x as anomalous. Many astronomers looked before through their telescopes at the quartile near Zeta Tauri and reported their observations to be the observation of a star.{15} Because discovering that something is the case is a matter of perspective, only recourse to ostensive aids is available. If a person claims not to see the particular aspect of the state of affairs in question one can direct him to look again, possibly adjust the particular instrument in question, be it a microscope or a telescope. If the person still doesn't see, then not much more can be done.

Once, however, it is recognized that a particular aspect of a state of affairs is a matter of fact which is anomalous, this is not the end but only the beginning of scientific research. The next step is very important for a scientist must specify what this x is. He must supply a description of x in the language of his scientific theory. To do this he might have to modify the language of his theory or at times invent a new theory in which such an x might be properly described. Priestley applied the phlogiston theory and called that particular gas, dephlogisticated air. Lavoisier, on the other hand, saw fit to develop a new theory in chemistry in order to adequately specify what this gas was. For him this gas was oxygen which was a "principle of acidity" and which was formed when that principle united with caloric. For most descriptions of what an x is no such drastic revisions are necessary. A good example of this can be found in the case of Herschel's discovery, who didn't need to invent a new category but had only to state that the object observed is a planet which will be called Uranus. Here the category of "planet" was already available; the only problem was to ascertain whether object x satisfied the criteria of the concept of planet, i. e., whether x behaved like the other things called planets. Some discoveries involve the perception of anomaly but only a small number of these will require revision in theory and a still smaller number will lead scientists to the creation of a new theory. Accumulation of anomalies leads the dominant paradigm theory into crisis and ultimately to a revolutionary overthrow of the old paradigm and the adoption of a new theory as a paradigm. I find the above description of scientific change, including the stages of normal science, crisis, and revolutions helpful and illuminating except for the term "paradigm" which I will redefine in the second chapter.

Kuhn's talk of gestalt switches in describing what I have taken to be the first part of a scientific discovery is helpful, and appropriate since the first part of making a novel discovery in science usually requires change in perspective -- seeing at times the "same thing" as something else; But when Kuhn applies the notion of a gestalt switch to characterize the changeover from one paradigm- theory to another, I find such talk puzzling. Kuhn argues that:

Paradigms are not corrigible by normal science at all. Instead, as we have already seen, normal science ultimately leads only to the recognition of anomalies and to crises and these are terminated not by deliberation and interpretation, but by a relatively sudden and unstructured event like the gestalt switch. Scientists then often speak of the "scales falling from the eyes" or of the "lightning flash" that "inundates" a previously obscure puzzle, enabling its components to be seen in a new way that for the first time permits its solution.{16}

In the first place, gestalt switches are instantaneous. When a person undergoes a perceptual gestalt switch, he sees now one thing and now another, i.e. first an old woman and then a young girl.{17} Because they have that instantaneous character, it is hard to see the pertinence of the same description to paradigm-theory debates. The ultimate acceptance of a theory by a scientific community usually takes many years. One only has to look at Copernican heliocentric theory to realize the arduous stages that a theory had to go through before its ultimate acceptance. During this time, adherents of the theory try to develop arguments in support of the theory as well as answer the criticisms made by those who are opposed to the new theory.{18}

I will argue later that Kuhn himself seems to believe that scientists do develop arguments in support of their theories. Some of these arguments are in part dependent on the theory and as a result are circular. The circular nature of these arguments will not persuade those who do not want to step into the circle, i.e. accept the premise whose truth depends on the theory in question. But besides these circular arguments, Kuhn also believes that scientists can develop arguments that are not circular in the above sense. Such arguments cannot always be developed, but when their development is possible scientists know that these arguments have a very high persuasive power. Thus, arguments which exhibit greater predictive accuracy of theory A over theory B are very convincing.{19}

In view of the above consideration I don't find Kuhn's use of gestalt switches very illuminating when it comes to the problems surrounding theory change. I do think that, as I have already pointed out, something like a gestalt switch seems essential to the perception of some scientific discoveries. What I suspect happened is that since Kuhn has rightly argued that gestalt switches are relevant in seeing that something novel is the case, he felt that it also can characterize the whatness of this novel phenomenon. But whereas the first part of the discovery is perceptual, the second part is more linguistic and mind dependent. If the characterization of the whatness of this phenomenon requires the development of a new theory with its own theoretical language, then the adoption of this theory will not depend on a gestalt switch since it isn't solely a perspectival matter but concerns the usefulness of this theory and of the plausibility of this way of speaking about the phenomena in question.

Some have thought that to believe that observation reports are theory-laden entails a relativistic position in science. To explain my position on this question I would like to address myself to the following questions: 1. Does the claim that there is no neutral observation language imply that there is no independent and objective reality which must be taken into account by our scientific theories? 2. Does it imply that there is no independent check on the creation of our conceptual schemes? I don't think that either of these questions need be answered in the affirmative.

We need not look very far to see how observation reports, even though they are couched in the language of the dominant theory, can still lead that theory into crisis and ultimate rejection. The predictions and anticipations created by a scientific theory extend far beyond the evidence at hand. Usually it extends to phenomena which have as yet been unobserved. Because of this fact, such predictions, when they are in error (i.e., when an observation report contradicts the statement that the theory projected) alert the scientist to be on the look-out for errors on various fronts. It could be that an error was made in the observation report, in which case the theory stands as stated. Or, should more observation reports be in opposition to the predictions of the theory (i. e., should more anomalies arise) then the theory must be either modified or replaced by another theory which explains these anomalies (that lead the older theory into crisis.) If we look at the phlogiston theory again, we can see how Lavoisier's report, that certain metals upon calcination gained weight, ultimately led to the rejection of the phlogiston theory and acceptance of Lavoisier's oxygen theory.

In the case of discovery of novel phenomena, of a discovery that there is a new kind of thing in nature, we also can come to the realization of its existence even though we can't even describe it in the language of our dominant theory. The phenomena of gain in weight when none was expected could at least have been characterized in terms of the categories of ordinary discourse. But in the case of the discovery of x-rays such a description was not as readily available. Here again nature did not want to be confined within the limits of our newest theories. Roentgen was investigating the well known phenomenon of cathode rays when he noticed that his barium platinocyamide screen glowed when it shouldn't have. Novel phenomena can be recognized even though it isn't predicted or anticipated by our theories. There are times then, when certain aspects of states of affairs can be observed as a matter of fact even though they defy description in the terminology of our dominant scientific theories. This idea can be put in the following way: that we can't in this case as yet make a statement of fact about this matter of fact.{20}

In view of the above observations, some passages in Kuhn become much more plausible. Towards the end of his book Kuhn states:

Those theories, of course, do 'fit the facts' but only by transforming previously accessible information into facts that, for the preceding paradigm, had not existed at all. And that means that theories too do not evolve piecemeal to fit facts that were there all the time. Rather, they emerge together with the facts they fit from a revolutionary reformulation of the preceding scientific tradition, a tradition within which the knowledge-mediated relationship between the scientist and nature was not quite the same.{21}

Since part of a discovery is a specification of its whatness, as I have indicated previously, we have here a ready interpretation of Kuhn's statement that "that means that theories too do not evolve piecemeal to fit facts that were there all the time. Rather, they emerge together with the facts they fit from a revolutionary reformulation of the preceding scientific tradition."

By "facts" above Kuhn means statements of facts that are not merely an observation that something is the case but more importantly for scientific purposes the specification of its whatness using the theoretical terminology of the scientific theory in question. During stages of revolutionary discoveries, where such discoveries cannot be adequately described in the old paradigm-theory, a new theory must be developed. Thus, we see in what sense some statements of fact do emerge together with the new theory.

Theories, to be acceptable, must incorporate most of the observational data which is at the disposal of the scientist, and, as I have pointed out, the newly emerging theory usually will "fit the facts" in part because the theory was developed in order to explain, and to characterize, the whatness of a discovery.

I think that enough examples have been given to illustrate how observation reports, even though theory- laden can and do place limitations on our theories, on our conceptual schemes. Because of this, Thesis 2 does allow for the possibility of objectivity in scientific change. Much more, however, needs to be said before reason and objectivity will be shown to dominate in scientific change.

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{3} For further reference see footnote 6 on page 4. [Back]

{4} Norwood Russel Hanson has earlier argued at length a thesis very close to that of Professor Kuhn. He states that, "There is a sense, then, in which seeing is a 'theory-laden' undertaking." Patterns of Discovery (Cambridge: University Press, 1965), p. 19; see also p. 30, footnote 1; also p. 56.

Israel Scheffler in his most recent book also holds the view that observation cannot occur apart from conceptualization. In summarizing his view he states:

"It will be well to summarize our findings concerning the independence of observation at this point, . . . We have first of all, denied that observation is carried on in actual isolation from processes of conceptualization. We have, furthermore, denied that what is observed is unalterable by conceptual change. We have, thirdly, denied that what is given to observation is ineffable. Finally, we have denied that observational descriptions are certain, and we have charged with meaninglessness the notion of error-free sensuous content." Science and Subjectivity, p. 36. [Back]

{5} SSR, p. 125. [Back]

{6} Thomas Kuhn "Historical Structure of Scientific Discovery," Science, CXXXVI, 3518 (June 1, 1962), 760-764, 762.

Also "Only when all the relevant conceptual categories are prepared in advance, in which case the phenomenon would not be of a new sort, can discovering that and discovering what occur effortlessly, . . . " SSR, pp. 55-56. [Back]

{7} The above story of the discovery of oxygen is a summary of the story as presented by Kuhn in "Historical Structure of Scientific Discovery." For a more detailed discussion of this period see James B. Conant and Leonard K. Nash (ed,) Harvard Case Histories in Experimental Science (Harvard University Press, 1957), Vol. 1, "The Overthrow of the Phlogiston Theory; The Chemical Revolution of 1775-1789," ed. by J. B. Conant. [Back]

{8} Harvard Case Histories in Experimental Science, p. 72. [Back]

{9} Ibid., p, 73. [Back]

{lO} Harvard Case Histories in Experimental Science, Vol, 1, p. 77. See also p. 79. [Back]

{11} "Historical Structure of Scientific Discovery," p. 762. [Back]

{12} Quoted by Kuhn, Ibid., p. 762. [Back]

{13} Ibid., p. 764. [Back]

{14}In a recent illuminating article, George L. Farre, using partly his own terminology also stresses the importance of the perspective in identifying that some new matter of fact is to be identified. He states:

"By d1 I mean the empirical discovery of a new mofal (matter of fact) structure, that is, of a new kind of fact, what Hanson would call a "new pattern", because of the perspectival aspect of mofs (matter of fact), d1 is tantamount to the discovery of a new way of looking at the world, that is of organizing our experience. In the context of science, this form of discovery is the most revolutionary, having far-reaching consequences, extending often to cognate disciplines. In fact, it may be short of an intellectual revolution, working, as it were, a cultural mutation."

George L. Farre, "On the Linguistic Foundation of the Problem of Scientific Discovery." Journal of Philosophy, LXV, 20 (Dec. 19, 1968), 779-794, see p. 788. [Back]

{15} Hanson quotes Herschel as saying:

"An object is frequently not seen from not knowing how to see it, rather than from any defect in the organ of vision . . . {Herschel said} . . . I will prepare the apparatus, and put you in such a position that {Fraunhofer's dark lines} shall be visible and yet you shall look for them and not find them: after which, while you remain in the same position, I will instruct you how to see them and you shall see them, and not merely wonder you did not see them before, but you shall find it impossible to look at the spectrum without seeing them.

Patterns of Discovery, p. 184 footnote. [Back]

{16} SSR, p. 121. [Back]

{17} Hanson, Patterns of Discovery, pp. 11-13. [Back]

{18} Kuhn, himself, has said as much in his other book, The Copernican Revolution. [Back]

{19} See Chapter II, section 3 on the circularity thesis for other types of arguments which are not paradigm-determined. [Back]

{20} This terminology is clearly described in George Farre's recent article "On the Linguistic Foundations of the Problem of Scientific Discovery," Journal of Philosophy, LXV, 24 (1968), 779-794. [Back]

{21} SSR, p. 140. [Back]

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