The classical empiricists recognized that empirical observation was not foolproof. They knew the error that optical, aural, and other sensual illusions could bring. The epistemological rationalists (e.g., Descartes, Spinoza, Leibniz) played on the uncertainty brought about by the possibility of illusion to criticize empiricism as a philosophy of knowledge. Classical empiricists, however, did not presume—as the rationalists did—that knowledge must attain absolute certainty to qualify as true knowledge. The fact that we know we can be fooled by illusions, can recognize and fix that type of error, must mean that we can improve our perception and understanding. If we can look back and know we were fooled, with clearer perception or understanding, then even with the possibility of sensual illusions, empirical observation must be a strong enough standard for knowledge. However, as we will see, sensory illusions are only one type of challenge a fundamental reliance on empirical observation faces.

A PARADIGM CASE: TERRI SCHIAVO

Let us begin with a story with which most of us are likely generally familiar. In 1990, 27-year-old Theresa Marie Schiavo suffered cardiac arrest. She was eventually diagnosed as being in a persistent vegetative state due to anoxia, secondary to the cardiac arrest. A persistent vegetative state is a type of cognitive pathology in which a person is awake but not aware. It is distinct from a coma in that the comatose patient is neither awake nor aware. The vegetative person may open his or her eyes and experience normal sleep cycles but lacks all cognitive function. The vegetative person has no consciousness as we understand consciousness in the human sense. She may respond to some external stimuli, such as tracking objects with the eyes, but has no experiential or cognitive understanding of those stimuli. Some patients recover from a vegetative state after a few weeks. However, the longer the patient is in a vegetative state, the less likely recovery is expected. After 1 year, the state is referred to as a permanent vegetative state (Jennett, 2002, p. 59). Hence in 1998, apparently accepting the irrevocable nature of his wife’s condition, Michael Schiavo requested that Terri’s feeding tube be removed to allow her to die on her own. Terri’s parents, the Schindlers, disagreed with this decision, as they did not accept the vegetative diagnosis and the grim prognosis that accompanied it. In order to garner sympathy and support from the public, the Schindlers posted videos of Terri on the web. These videos showed Terri appearing to respond to the presence of her parents, watching the motion of a balloon, in general seeming to demonstrate the consciousness that a vegetative person would not have. Thousands, if not millions, viewed these videos on the web, including members of the U.S. Congress. As this case became a political issue, physician-Congressmen Bill Frist (R-Tenn.), Dave Weldon (R-Fla.), Joe Schwarz (R-Mich.), and Tom Price (R-Ga.) denied the vegetative diagnosis based on their viewing of these videos (Annas, 2006). Some viewed the videos of Terri Schiavo and saw a vegetative patient. Others viewed the videos and saw something different. This is the essential problem with observation in general: the possibility of two perceivers viewing the visual stimulus yet seeming to see different things. This possibility further challenges the presumed objectivity of science itself. As we will see there may be several reasons why two people viewing the same thing may see different things.

SOME BASIC PROBLEMS

Optical Illusions

Before delving any more deeply into our paradigm case, let us take some simpler, classic cases of people seeing different things. One of these cases involves the Necker Cube (Figure 9.1).

As the two pictures in Figure 9.2 demonstrate more clearly, there are two distinct ways to perceive this drawing: as a cube in which the cube is angled toward the left and one in which it is angled toward the right. Indeed, the same viewer can perceive the cube in both ways, but not simultaneously. With a little concentration, you can watch the cube switch back and forth—what is called flipping a Gestalt switch (Kuhn, 1962, pp. 85, 111–114). But the mysterious thing is that when flipping this switch, the external visual stimulus you receive does not change. And when one person sees it as it appears on the left and another as it appears on the right, again they are receiving the same visual stimulus. These facts point to the conclusion that an important part of seeing depends on something that occurs inside of us and not simply what visual array of light rays reaches our eyes. Another famous example like this is the duck–rabbit drawing (Figure 9.3). At one moment it may appear to be a rabbit with its mouth to the right and its long ears pointing horizontally to the left. At another moment it might appear to be a duck with its bill on the left.

FIGURE 9.1    Necker Cube 1.

Source: Necker Cube (2009).

FIGURE 9.2    Necker Cube 2.

Source: Necker Cube (2009).

FIGURE 9.3    Duck–Rabbit.

Source: Rabbit–duck illusion (2010).

Now, one might protest that examples like these are quaint and even interesting, but they are artificial and intentionally designed optical illusions and not necessarily relevant to real-world perceptions. This may be so, but nonetheless they point to a variability in perception that does not depend on external sense data. Seeing this drawing in two different ways is called flipping a “gestalt switch” due to their development by Gestalt psychology. Gestalt psychology (about which more will be said later) challenged the commonsense view of seeing. The commonsense view of seeing (and also the one seemingly held by classical empiricists and many other empiricists) is that the eye works simply like a camera: absorbing sensory information. Thus, just like a pair of cameras, “two people viewing the same object under the same circumstances … will ‘see’ the same thing” (French, 2007, p. 62). Yet what these two examples (and there are countless many others) begin to show is that there is something wrong with this commonsense view. Furthermore, as Kuhn (1962) maintained, in real life Gestalt switches are flipped as well.

Real-World Ambiguities

For a real-world example, Norwood Hanson (1965) asks whether 17th-century astronomer Johannes Kepler and 16th-century astronomer Tycho Brahe “saw” the same thing when they looked up at the sun. The complicating factor is that Kepler held a heliocentric theory while Brahe held a geocentric theory. Hanson’s answer to this question is yes and no. When each of these men looked at the sun they had the same “retinal reaction” (Hanson, 1965, p. 6). Their eyes absorbed essentially the same sense data. On that level, they saw the same thing. However, that is not all there is to seeing. For, “seeing the sun is not seeing retinal pictures of the sun… . Seeing is an experience. A retinal reaction is only a physical state” (Hanson, 1965, p. 6). Hanson makes a quasi-phenomenological point here. Contrary to the classical empiricist presumptions, seeing (or indeed hearing, smelling, tasting, and tactilely feeling as well) is more than the accumulation and absorption of sense data. It is an experience of the person, not merely a function of the senses. It is an experience that persons have as persons, not merely as collections of sense organs. Because of differing theoretical presumptions, when Kepler and Brahe looked at the sun, there is a sense also in which they saw different things. For Brahe, the sun was but one of many bodies that revolved around the central (and thus cosmically important) earth. For Kepler, the sun held a central and thus more important place in the universe. Hence, even though they took in the same sense data and had the same retinal reaction to these data, the objects that they, as persons (not merely as sensory input machines like a camera), saw were different.

For a related example, consider an x-ray as viewed by a medical student and the same x-ray viewed years later when the student is an experienced physician. The student might see a representation of the inside of a particular person. This seems correct. And this is also what he will see as an experienced physician. Yet, as an experienced physician, there is much more that he will see. There are anomalies and pathologies that remain indistinct and essentially invisible to the student. The elements of their visual fields are the same, but they are not organized the same: “the same lines, colours, shapes are apprehended by both, but not in the same way. There are indefinitely many ways in which a constellation of lines, shapes, patches, may be seen” (Hanson, 1965, p. 17). There are some similarities and differences between the Brahe/Kepler example and the x-ray example, as well as between these two and the optical illusions raised earlier. Clearly, with the x-ray example there is a difference in knowledge that affects perception. Part of the reason the physician sees something different is that he has gained in knowledge over the years and come to recognize subtleties in an x-ray that he as a student did not see. One might say this of the difference between Kepler and Brahe as well, but the situation is a little different. In Brahe’s time, geocentrism was the largely accepted theory. In Kepler’s time, heliocentrism began to find greater acceptance. So each was working with what was considered knowledge and truth in their times. Yet, from our point of view, we might now be tempted to analogize Kepler with the physician and Brahe with the naive, ignorant medical student. If we want to find a difference between these examples it might be that in the Brahe/Kepler example the difference is one of theoretical presuppositions, whereas in the x-ray example the difference is one of knowledge. This difference breaks down, however, if we come to understand that any claims to knowledge presuppose some theoretical commitments. Comparing these examples with the optical illusions of the Necker Cube and the duck–rabbit, it does not seem that any particular knowledge or theory determines which cube or which animal is perceived. The drawings themselves are designed in an ambiguous fashion and sometimes called multistable projections (French, 2007). Yet, on another level, previous knowledge or theory does seem necessary. In order to view the Necker Cube and see a cube at all, one must first have Western conventions of perspective internalized as part of the way one sees the world, because, literally speaking, the Necker Cube is not a cube. It is a pattern of intersecting and overlapping straight lines on a two-dimensional surface. A cube is a three-dimensional shape. One not culturally assimilated with Western conventions of perspective may see nothing more than intersecting and overlapping straight lines. No one who has not seen ducks or rabbits—or both—or animals similar to ducks and rabbits will see what most of us see when looking at the duck–rabbit picture. It may just be an odd, indefinite shape. Another difference between the later examples and the multistable projections is that with the multistable projections there is a third perspective to be had over and above the two possible and ambiguous perspectives: a perspective that recognizes both perspectives, the ambiguity of the image. With the Brahe/Kepler example and the x-ray examples, that third, outsider perspective does not really exist, which may lead us down the dangerous road of relativism.

When presented with these ambiguities, a common response is to draw a line between “seeing” and “interpreting” so that everyone sees the same cube but interprets it as one type of cube or another. Everyone sees the same duck–rabbit drawing but interprets it either as a duck or a rabbit. Brahe and Kepler see the same sun but interpret it differently. The medical student and the physician see the same x-ray, but the physician has the requisite experience and cognitive tools to interpret the content of the x-ray. This approach has the benefit of preserving some sense of brute facts. Lying beneath all these interpretations are the same perceptions, the same brute facts. This approach seems to retain the universality and objectivity presumed by empiricists. Hanson, however, argues that this distinction does not apply to what we are discussing here. There are times of course in which we interpret what we see. On a foggy night, seeing an indistinct figure in the distance, one might have to interpret this blur of a perception to make sense of it. Once the object is nearer and clearer, one’s interpretation will be confirmed or denied. This example brings out the point, the difference that demonstrates why this distinction does not help us here: “To interpret is to think, to do something; seeing is an experiential state” (Hanson, 1965, p. 11). When Brahe looked at the sun, he did not have a retinal reaction to a stimulus and then apply a theory to that reaction. Rather, his geocentric theory shaped the experience he had of that visual stimulus. When Kepler looked at the sun, he did not have a retinal reaction to a stimulus and then apply a theory to that reaction. Rather, his heliocentric theory shaped the experience he had of that visual stimulus. They both simply saw the sun—though what each understood as the sun differed and led to different visual experiences of the sun.

The x-ray example provides some interesting complexities. On the one hand, it is true that when the physician views an x-ray he sees something different than the medical student and that difference is not due to a difference in interpretation. On the other hand, oftentimes with x-rays some actual interpretation is necessary. Sometimes viewing an x-ray is more like seeing an indistinct figure on a foggy night. And like the indistinct figure on a foggy night, the radiologist’s interpretation might only be confirmable (or deniable) through a closer look (exploratory surgery perhaps). But separate and prior to these indistinct or ambiguous images, a seasoned radiologist will look at an x-ray and see something very different from what a medical student, or even a physician of a different specialty, will see. But still, the radiologist just sees the x-ray. She does not see and interpret the x-ray, unless an indistinct or ambiguous image is determined to be in need of interpretation. Analogously, a trained musician may be able to hear an out-of-tune oboe in the midst of an orchestra, where such a subtlety is lost by the average music lover (Hanson, 1965, p. 17). The musician does not hear and interpret the intonation problem. He simply hears it, whereas many others receiving the same auditory sense data do not. Similarly, the wine aficionado can detect subtle differences in high-quality wines that are lost by most wine drinkers. The better paradigm case of “seeing,” according to Hanson, would not be the reception of sense data, such as patches of color, as the classical empiricists maintained, but seeing what time it is (1965, p. 16). Once a theory and practice of timekeeping is internalized, one does not see the clock and interpret the time. One simply looks at the clock and sees the time. Similarly, for anyone fluent in speaking and reading English it is impossible to look at the marks on this page as mere marks. Seeing the marks is seeing the words. We challenge any reader right now to separate the visual experience of these marks from the apprehension of words.¹

Philosophers of science refer to this quality of observation being affected by background knowledge and theory as the theory-laden quality of observation. That is, whenever we observe anything, or more generally perceive anything, there is an inseparable theory and background knowledge that will shape that observation. Even when we try to separate observation from theory we run up against an infinite regress (Popper, 1935/2002, p. 75). We take a particular observation, identify the theory(ies) that underlies it, then identify the observations that support that theory(ies), then identify the theory(ies) that underlies those observations. We never reach bedrock, brute facts. This lack of brute facts is a challenge to the presumed universality and objectivity of science. How do we address this lack of bedrock and possible relativism? We will address that question later. First, there are some further problems of observation we must look at.

FURTHER PROBLEMS

Presumptions and Prejudices

There is a similar problem to this theory-laden problem that was raised in Chapter 8. Under most contemporary conceptions of the scientific method, a scientist brings to any experiment, any attempt at observation, a specific hypothesis—a provisional answer to the question at hand. The presumptions that in part comprise this hypothesis may well skew the scientist’s perception. He or she is more likely to see what he or she expects given the presumptions of the hypothesis. This does not mean that he or she will only see results or data that will confirm his or her hypothesis. What it means is that what counts as either confirming or refuting data will itself be based on certain presumptions and may limit what the scientist sees. This may be even truer today with the aforementioned reliance on technology. A particular instrument may truly only be capable of revealing certain types of data—the type of data that of course the experimenter presumes will be present. Other types may escape detection by the instrument. Advocates for creationism and intelligent design will point to these types of presumptions to attack the presumed objectivity of science in general and evolutionary theory in particular. The claim of course is that modern biologists are so imbued with evolutionary theory (and the hypotheses with which they design their experiments so constrained by it) that they are constitutionally unable to detect any data that would be inconsistent with the presumptions of evolutionary theory, thereby calling into question the presumed objectivity of science, especially evolutionary theory (Intelligent design network, 2005). But as noted in Chapter 8, there is a practical purpose to the use of hypotheses and even the limitations on perception that they impose. Without such limitations defining relevant data, data collection would be endless and without form. Hypotheses direct observations. This problem is really a more patent manifestation of the theory-ladenness of perception. For, when we say that a hypothesis brings with it certain presumptions, what we are talking about is a certain theory (or set of theories) about the way the world works when informing and giving meaning to observations and observation statements. By extension then, theory-ladenness is not really an obstacle to observation but is in fact necessary to observation. Background theory and knowledge provide context and form for observation. Without this background, according to Thomas Kuhn, our experience would be as William James described that of a newborn baby: “a bloomin’ buzzin’ confusion” (Kuhn, 1962, p. 113).

Movements in 20th-century psychology also note, develop, and explain some of these problems of perception. Gestalt psychology was developed as a response to structuralism, which understood perception in a manner quite similar to most philosophical empiricists: We perceive the world analytically as an aggregated collection of sense data. Gestalt psychologists like Max Wertheimer (1880–1943) endeavored to show that perception did not work that way. According to Gestalt psychology, we do not perceive discrete quanta of sense data that we then place into larger contexts—like Locke’s theory of simple and complex ideas. Rather, what we perceive are complex wholes that have a meaning transcending their discrete parts. Contrary to Locke’s theory we do not perceive coldness, hardness, and wetness and place these into a whole that we call an ice cube. Rather, what we perceive is an ice cube. We might then, as a matter of analytical thought, reduce the ice cube to its constituent parts. We see wholes in a context of theory, not “piecemeal or item by item” (Kuhn, 1962, p. 128).

There is a famous story about Galileo often raised as an illustration of close-mindedness and a lack of critical reasoning (see, e.g., Copi & Cohen, 2002, pp. 139–140). From ancient Greece until the beginning of modern science the heavenly bodies (planets, stars, the moon, etc.) were thought to be just that—heavenly, divine bodies, part of a perfect realm beyond and separate from this imperfect world we will live in. Because the heavens are perfect, heavenly bodies must be in the most perfect shape. According to ancient Greeks, that would be a perfectly round sphere. Many of Galileo’s colleagues still thought in this manner. Thus, when Galileo looked through his telescope and reported observations at odds with traditional beliefs about the heavens (e.g., a moon pitted with craters and valleys, rather than being perfectly spherical) many of his colleagues refused to accept his findings. At first blush it might seem ludicrous to deny such facts—especially given our position now in which these claims about the heavens are undisputed common knowledge—that these Schoolmen were simply being dogmatic, arrogant, ignorant, and refused to believe what was plainly before their eyes. Yet, to be fair, we can try to look at the situation more from their perspective. The telescope was a new and mysterious instrument at the time. An adequate theory of optics did not even exist to explain how the instrument worked or justify the authority and authenticity of the images seen through it. With this in mind, some degree of skepticism seems reasonable. Such skepticism can be given further support when we compare Galileo’s drawings of the moon as seen through his telescope to later drawings and contemporary photographs of the moon and see the differences between Galileo’s perceptions (Figure 9.4; Siderius Nuncius, 2015) and a modern photograph (Figure 9.5; Moon, 2015).

Although Galileo’s drawings are more similar to the modern telescopic images of the moon than would be the image of a perfect sphere, they are different enough to demonstrate the inaccuracy of his perceptions. To dismiss Galileo’s detractors may mistakenly assume that there is some privileged perspective, as there is with the multistable projections, from which to judge differing observations.

Observational Prostheses and the Observation–Theoretic Distinction

This story raises the further problem that in modern science much observation is done not by the naked eye but through various forms of technology: microscopes, telescopes, x-ray machines, MRI, neutrino detectors, and so forth. Some of these devices seem like pretty straightforward visual prosthetic devices (microscopes and telescopes), while others seem like more abstract forms of observing (neutrino detectors). Yet the straightforwardness of microscopes and telescopes can be misleading. For, even with those relatively simple devices, some distortion of what is being seen (e.g., refraction) is inevitable. All these instruments seem to place something between us and the thing to be observed that may justify a certain degree of skepticism toward the accuracy of the image. For those with experience with microscopes, think of your first time looking through a microscope. You likely saw nothing recognizable. You had to “learn” how to see through a microscope. This common experience suggests that microscopes (and other such devices) are not simple, straightforward visual prosthetic devices. They are tools that affect and change the world. Yet in modern science such tools are indispensable.

This necessity of observational instruments and the problem mentioned earlier that it raises point to an even deeper problem of observation in modern science. Much of what modern science studies is not directly observable. The most obvious example is subatomic particles. The problem with some such particles is more than a technological one. Even if adequate magnification were possible, some particles, such as electrons, would still not be visible, as light rays cannot reflect off of them. We can observe what might be called the effects of electrons, such as a vapor trail in a cloud chamber. Here, though, many would say that we are not observing the electrons but inferring them from their effects, or at best indirectly observing them. Electrons and other subatomic particles are often then put into a class of what are called “theoretical entities.” These are contrasted with “observable entities,” which are directly observable, at least in principle if not in practice. This problem became especially troublesome for the logical positivists because they endeavored to maintain a strict empirical outlook, yet they were especially inspired by modern physics, which focuses on many nonobservables. So the problem they faced was how to maintain a strict empiricist approach while allowing for the positing of unobservable entities.

FIGURE 9.4    Galileo’s drawings of the moon.

Source: Siderius Nuncius (2015).

FIGURE 9.5    Modern telescopic photo of the moon.

Source: Moon (2015).

To understand the logical positivist response to this problem, the first thing to remember is the school’s emphasis on language. All claims to knowledge are expressed as statements. Thus, when we say we know something, what we know immediately is a statement or sentence. How do we know if any statement or sentence is true? Sentences are justified by other sentences. But ultimately we must reach some basic sentence (sometimes called a protocol sentence or atomic statement), which is directly related to a particular sense experience—a line of thinking obviously adapted from the classical empiricist (especially Humean) thesis that all meaningful concepts must be traceable to a sense impression. This sense experience was, for logical positivists, what gave claims to knowledge ultimate justification and authority. This seemingly simple process is made more complicated once a distinction between an observation language and a theoretical language is introduced: the recognition that there seems to be something different in principle between the way we talk about observable and theoretical entities; that is, a difference between observation and theoretical statements. Theoretical statements refer to theoretical entities, which are not directly observable. To make theoretical statements meaningful, they must be derivable from protocol sentences and ultimately the brute facts of basic sense experiences. However, as we have seen, due to the theory-ladenness of observation, such brute facts are not forthcoming. The logical positivists did not of course recognize this theory-ladenness and assumed that perception was unaffected by theoretical beliefs and was “a source of neutral data that could be used to adjudicate among competing theories” (Schick, 2000, p. 164). Thus, to make theoretical statements (and ultimately theoretical entities) meaningful, the philosopher must “connect the observational components of a theory … with the theoretical components in order to insure … testability” (Matheson & Kline, 1998, p. 376). Yet, without appeal to the stability of brute facts the authority of protocol sentences has no basis and the very distinction between observation statements and theoretical statements begins to break down. Every observation statement implies a variety of other observation statements and theoretical presuppositions in support of it. What this means is that “No predicates, not even those of the observation language, can function by means of direct empirical associations alone” (Hesse, 1970/2000, p. 169). Like theoretical statements, observation statements are given support and meaning by a constellation of other statements and theoretical beliefs.

One can even take the erosion of the observation–theoretic distinction even further, as Dudley Shapere does, in arguing the counterintuitive primacy of theoretic language over observation (Shapere, 1982/2000). Because of the use of observational instruments noted before and the centrality of theoretical entities, “science has come more and more to exclude sense-perception as much as possible from playing a role in the acquisition of observational evidence” (Shapere, 1982/2000, p. 150). Ironically, what seems to have become more basic than direct perception through the senses is supposedly indirect perception through instrumentation. The authority of these instruments is dependent on (much the same but maybe more so) physical and other scientific laws. As new laws are discovered and old laws possibly revised or disposed of, the background knowledge that determines the authority of observation through instrumentation may change: “what counts as an observation, is a function of the current state of physical knowledge, and can change with changes in that knowledge” (Shapere, 1982/2000, p. 143). This realization leads us right back to the problem of relativism.

OBSERVING PERSISTENT VEGETATIVE STATE

In the Terri Schiavo case, particularly in reference to those videos on the web, we seem to be in a similar state as many of the examples discussed earlier. Some viewing those videos saw a woman in a persistent (or permanent) vegetative state (PVS). Others saw something different. Perhaps like Congressman Tom DeLay (R-Tex.), they saw someone merely “handicapped, like many millions of people walking around today” (Annas, 2006, p. 106). One basic problem that might be pointed out here is the mix of expert and lay observations. Because of the public nature of this case, many with no experience with patients with neurological deficits (such as Tom DeLay) felt license to make a diagnostic judgment based on their observations of the videos. Physicians are advised to pay attention to the observations of those caring for a patient over several weeks’ time, including nurses and family members, when considering a diagnosis of vegetative state—while keeping in mind the possibility of such observations being skewed by wishful thinking (Jennett, 2002, p. 23). So, lay observations are not wholly irrelevant, although the kind of sustained observations suggested are not the kind to be had through watching these videos. If it is true, as noted earlier, that background knowledge has an effect on observation, it would not be surprising that experts and nonexperts viewing the same videos might see different things. Yet, of course, as noted earlier, a number of physicians in Congress denied the vegetative diagnosis based on these videos. One response might be that, though physicians, none of these were in fact neurologists. They had some level of expertise as physicians but not that of one who specializes in neurological disorders. One might also impute some amount of political skewing and prejudice to these observations. Given that these were all Republican congressmen and that it was mostly Republicans who allied themselves with the parents of Terri Schiavo, there seems some substance behind this claim. These diagnoses by physician/congressmen raise another problem with observation in this case. Making a diagnosis purely on the basis of such videos is both epistemically and ethically suspect. There is no direct observation of the patient, only observation through the media of video and the Internet. Thus, as mentioned earlier, the inclusion of instrumentation between observer and observed allows for dubiety. Further, there is the possibility of editing and the selective use of cuts to be placed on the web that could skew perception. Not only the fact of instrumentation being inserted between the observer and the observed can cause doubt, but the nature of that instrumentation to allow for manipulation can raise further doubt about what one is seeing.

Ultimately, the problem with observing the vegetative state is that this state relates to consciousness. As such, it raises the issue known to philosophers as the “other minds” problem. We are intimately familiar with our own consciousness (our own mind, not to be confused with our own brain, about which most of us know little) but have no direct contact with the consciousness of any other person. This raises the specter of solipsism. That is, for all we know the rest of humanity surrounding us may be a horde of mindless robots and may not have the type of feelings, experiences, and inner life—in general, self-consciousness or self-awareness—that we do. One response to the other minds’ problem is that we can know others have minds by analogy. When we see others acting and reacting in manners similar to how we (as mind-having entities) act and react, we can infer that they do so also because they have minds. Leaving aside the problems philosophers have raised regarding this approach to the problem, we can note that neurologists will employ a similar standard in diagnosing vegetative state: “Much of the debate about diagnosis turns on what behaviours reflect cortical activity, and whether fragments of activity in the cortex necessarily indicates awareness—lack of which is the crux of the diagnosis of the vegetative state” (Jennett, 2002, p. 11). In simpler terms, people who have consciousness behave like people who have consciousness. Behavior is something we can see, whereas consciousness is not. Yet certain problems arise here. Can we assume that we know all the behaviors in which consciousness is manifested? Does this means of diagnosis reduce consciousness merely to its behavioral components? This is part of what makes a problem of the distinction of vegetative state from locked-in syndrome: a condition in which the “descending motor pathways from the brain are out of action” leaving the patient with little or no motor function but with sensation and consciousness fully preserved (Jennett, 2002, p. 20). If consciousness is to be inferred from behavior, yet a locked-in patient has no motor function, there will be no behavior to infer from, and such absence could lead to an inference of vegetative state. Behind the diagnosis of vegetative state lies a particular theory of consciousness, that consciousness includes certain subjective, mental states; that consciousness is somehow (in manners we do not fully understand) connected to brain states; that consciousness somehow transcends mere biological function; and so forth. Consciousness and, by extension, pathologies of consciousness like PVS become theoretical entities, not directly, empirically observable ones.

One might think that a simple solution would be to find pathological states of the brain to which PVS, could be correlated. The first problem with this proposal, however, is that such states have not been discovered. This is why PVS is a clinical diagnosis. The condition does not refer to any specific underlying pathological state of the brain. EEG, CT, MRI, and PET can all be used to observe states of the brain consistent with PVS, but none of these results (or any combination of them) are diagnostically conclusive (Jennett, 2002, pp. 25–28). Also, as noted earlier, these are tools of observation (like microscopes and telescopes) that place technology between the perceiver and the thing perceived, thereby inserting room for doubt considering what is being observed (recall Galileo’s inaccurate drawings of the moon seen through his telescope). Again, when we employ any of the diagnostic instruments mentioned earlier (EEG, CT, etc.), there is a plethora of theory lying behind our trust in these instruments and our perception of the information they give us—indeed, our perception that what they provide us is indeed information. It seems that certain pathological states of the brain can be identified on autopsy as indicative of PVS, but that is of no help in diagnosing a still living patient (Jennett, 2002, pp. 51–56).

But the deeper problem is that we must remember what is under consideration here is consciousness, and none of these tools or tests “directly reflects consciousness” (Jennett, 2002, p. 28). Consciousness is a function of the mind that seems connected to but not defined by states of the brain. Minds are not (strictly speaking) observable (brains are, minds are not) and neither is consciousness. Just as a diagnosis based on behavior has its limitations, one based on these diagnostic tools has even further ones—even though on the surface they might seem more “scientific,” more objective, more sophisticated. None of the results that we can attain from such tests are backed up by our long-held views (theories) of what consciousness is, whereas a behavioral diagnosis can be. This is due in part to the newness of these tools. In the future, our theory of consciousness may change such that these tools are a more direct reflection than our observation of behavior.

Only gold members can continue reading. Log In or Register to continue

Share this:

• Click to share on Twitter (Opens in new window)
• Click to share on Facebook (Opens in new window)

Related

Related posts:

1. Philosophy of Science in a Practice Discipline
2. What Is Science? The Problem of Demarcation
3. The 100-Year Path to Nursing Science, 1910 to 2010: With Epilogue, 2010 to 2015
4. Philosophies of Social Science

Stay updated, free articles. Join our Telegram channel

Join