Escape from Vienna
Critical Reflections on a Lingering Confinement
by Patrick Henry Reardon
Until very recently I taught several divisions of the basic “Introduction to Philosophy” college course every semester, including summers, for ten years, and I am convinced that the average incoming college student is a thoroughgoing Logical Positivist. That is to say, he is persuaded that the only things he can know for certain are either objects available to his senses or matters under the control of his reason. Consequently, when I explain to him the meaning of Logical Positivism, he immediately recognizes it as the scientific disciplinary system he learned in his high-school science courses. This comes as no surprise, for I have not the slightest doubt that the “working philosophy” of the average high-school science teacher is still burdened by the inadequate epistemology of the Logical Positivists, whether he knows it or not.
Logical Positivism is a school of philosophy (really, a philosophy of science) that owes its origin to a group of Austrian thinkers, known as the Vienna Circle, in the early and mid-twentieth century. It is also a school of thought that the academic community itself has already rejected and that relatively few folks nowadays could even identify by name. The Vienna Circle may as well be a racetrack, as far as most people know.
Why, then, should I beat a horse whose death certificate the veterinarian, some time ago, already signed? Because reports of the old nag’s death are greatly exaggerated, and she is in fact yet running around here and there, and a lot of betters are still laying their money on her. Since some of these betters today even include Christian apologists, I propose to undertake a description and critique of Logical Positivism in the interests of helping us see its dangers and its confinement.
Logical Positivism Described
During much of the twentieth century, the philosophy of science in the United States was dominated by members and disciples of the Vienna Circle. Among their names are Kurt Gödel, Otto Neurath, Moritz Schlick, and Friedrich Waismann. Worthy of more special mention are Herbert Feigl (1902–1988) and Rudolph Carnap (1891–1970), inasmuch as these two, in the 1930s, immigrated to this country and began their very successful careers as authors and college professors. They and their graduate students in philosophy, many of whom followed them in teaching the philosophy of science in major universities throughout the United States, are to be counted among the major influences on the academic development of the sciences in this country. Since he wrote directly in English, the name of A. J. Ayer should be added to theirs as a fellow traveler of the Vienna Circle; his seminal work, Language, Truth, and Logic was published in 1936.
The proper task of philosophy, according to Logical Positivism, is epistemological—to establish the conditions of certainty. How, these men asked, can the mind become certain of the truth or falsehood of any given proposition? The very name “Logical Positivism” indicates their answer to the question, for it testifies to the two components of this philosophy’s methodology. The word positivism refers to the process of gathering empirical data, the investigation and critical assessment of sense knowledge. This is what Feigl calls “material science.” The word logical, on the other hand, refers to the organization of that empirical data by means of theorem and formal logic. This is what Feigl calls “formal science.”
Their answer to the question—How can the mind become certain of the truth or falsehood of any given proposition?—is that there are only two ways: either by the convincing accumulation of empirical knowledge, and/or the application of a valid rational inference.
Moreover, for the proper governing of this philosophy of science, the Logical Positivists recognized two “principles,” as they called them, the principle of intersubjectivity and the principle of verification. Both of these need to be examined in detail.
First, the principle of intersubjectivity means that, in the pursuit of “cognitive meaning” (Carnap’s expression), one may never appeal to a source of knowledge that is not universally available. We may think of this as a kind of democratic principle. It simply insists that each human mind, because it has the same structure, composition, heuristic processes, and logical procedures as every other human mind, must have equal access to exactly the same cognitive meaning. Thus, it is not legitimate for a person to appeal to some special heuristic or cognitive process not universally available. An obvious example of the latter would be an appeal to special revelation, which happens to be a distinguishing characteristic of the great Western religions. Thus, for instance, it is on the basis of this principle of intersubjectivity that scientists and others have opposed any introduction of religious doctrine or presupposition into the teaching of science in our public school systems.
The second principle of Logical Positivism is the principle of verification, or, as Carnap later called it, the principle of confirmation. This latter principle has to do with the methods of rendering knowledge certain. Like the principle of intersubjectivity, it is also an epistemological principle. With respect to verification or confirmation, Logical Positivists recognize two methods, the one positive and the other logical. Something is verified logically if it is deduced from mathematics or a valid syllogistic demonstration. Something is verified positively when it is established by recourse to empirical experience. It is worth noting here that Carnap includes the findings of psychology among the information that can be empirically verified. This means that, for Carnap, the propositions of psychology can be confirmed on the same basis as propositions of chemistry, biology, and physics.
Thus, according the Logical Positivists, there are only two types of propositions that can correctly be said to have “cognitive meaning”: analytical propositions and synthetic propositions. An analytical proposition is any proposition of which the truth value can be known simply by logical analysis. Take, for instance, such propositions as “the trilateral is a triangle” or “the circle has no corners.” By a logical analysis, simply noting the meanings of the words, I know for certain that such propositions are true. They are true because they must be true; their internal symmetry is of such a kind as to preclude doubt. This feature is what has been called (by St. Thomas Aquinas, if memory serves) the fulgor veritatis rapiens mentis assensum—“the brightness of truth ravishing the assent of the mind.” Or, on the contrary, take such propositions as “2 + 2 = 5” or “There are 360 degrees in the combined angularity of the pentagon.” By plain logical analysis I know such propositions to be false. They are false because they must be false; they suffer from a radical contradiction or incoherence in the relationships of their component parts, whether between premise and inference (“2 + 2 = 5”) or between the subject and predicate (“The pentagon has the same angularity as the quadrilateral”). In cases of analytical propositions, then, the truth value of the proposition is determined a priori.
There is another way to assert that an analytical proposition is true or false because it must be true or false—through the logical relationship between the subjects and predicates of propositions. In a true analytical proposition (“The circle is round”), the predicate (“round”) of the proposition is already contained in or necessarily implied by its subject (“circle”). Here the truth of the proposition is perceived in the tautological relationship between subject and predicate. Likewise, in a false analytical proposition (“The square is round”), the predicate (“round”) of the proposition is logically contradictory to or incompatible with its subject (“square”). In summary, then, analytical propositions are either true by the principle of tautology or false by the principle of contradiction. This is the logical part of Logical Positivism.
A synthetic proposition, on the other hand, is a proposition of which we cannot know the truth value by logical analysis, so that we must go outside of the proposition itself in order to ascertain whether it is true or false. This kind of proposition is called synthetic precisely because it brings together, and forms a synthesis between, a subject and predicate that neither imply nor contradict one another. For example, “the circle is blue” is a synthetic proposition. I may logically analyze this proposition until I myself turn blue, but no amount of logical analysis will ever tell me whether it is true or false. I cannot know its truth value except by recourse to empirical verification. That is to say, I must examine the circle and see whether or not it is blue. If such recourse to empirical verification is available—that is, if I have eyes and access to the circle—then the proposition’s truth value is perceived. Otherwise, the truth value of the proposition “the circle is blue” is not something I can be said to know, because the proposition itself bears no known relationship to the circle. The proposition does not have what Carnap called “cognitive meaning.” This is the positive part of Logical Positivism.
A Lingering Problem
Logical Positivism has not been dominant in the philosophy of science for a generation or more. The proponents of Logical Positivism are all gone.
Other thinkers have replaced them. The present graduate student in physics or mathematics, for example, may never have heard of Rudolph Carnap or A. J. Ayer, whereas it is not at all unlikely that he has read Thomas Kuhn or Karl Popper or Willard Van Orman Quine. It is more probable that a class syllabus reading list nowadays will prescribe Feyerabend than Feigl. Or, if the student is truly fortunate, someone has obliged him to read Stanley Jaki.
All of this is to say that the philosophy of science has moved on. It has discovered Kuhn’s “paradigm shifts,” taken account of Polanyi’s “tacit dimension,” weighed the implications of Heisenberg’s “uncertainty principle.” Carnap and his accomplices have fled the scene of the crime.
Nonetheless, though the Vienna Circle may no longer be a big wheel, its influence lingers. In spite of all the changes on the philosophical scene over the past generation and more, it yet appears to me that some sort of recourse to these two principles of Logical Positivism, the principles of intersubjectivity and verification, is common and even universal among scientists today. Indeed, one has the impression that such recourse is virtually a defining characteristic of scientific pursuit. All contemporary scientific endeavor (as distinct from philosophical speculation), as far as I can tell, is based on the application of these two principles.
Likewise, the very limited epistemology of the Logical Positivists, because it is widely accepted as “scientific,” has in large measure been adopted as a standard in disciplines outside of pure science. These disciplines include, not only the obvious examples of psychology and the social and behavioral sciences, but also religious studies. Within that last category, moreover, one finds the influence of Logical Positivism even in contemporary Christian apologetics.
Let me cite an instance to illustrate the influence of Logical Positivism in this last point. The conservative Christian thinker and apologist, Alister E. McGrath, who would hardly be thought a disciple of Feigl and Carnap, nonetheless appealed to the strictures of their epistemology in a fairly recent essay that he wrote against the religious universalism of John Hick (in the symposium volume Four Views on Salvation in a Pluralistic World, Zondervan, 1995). Hick’s universalist religious theory, McGrath observed, fails to prove itself as “universally available public knowledge open to general scrutiny and critical evaluation.” By way of general comment McGrath then went on to remark:
Quoting Hick, finally, McGrath objected to his universalist religious theory in terms difficult to distinguish from Carnap’s objections to metaphysics:
In this example provided by McGrath’s argument, it is clear that an epistemological theory that began as an aspect of scientific discipline has now found its way into an area of investigation far beyond what is normally thought of as science. In spite of everything, then, it would appear that the Vienna Circle is still making its rounds.
A First Critical Question
I come now to a critical analysis of Logical Positivism. I propose to begin by addressing two questions with respect to the application of its two principles, the principles of intersubjectivity and verification. First, are these two principles adequate? Second, are they exclusive?
First, are these principles adequate? To answer this question, I propose the two following considerations. First, intersubjectivity and verification do not seem to be epistemological principles, in the strict sense of being self-evident. That is to say, they do not appear, in themselves, to constitute tautologies; they are not so obvious as to constitute solid starting points for the acquisition of knowledge. I take the two alleged principles individually.
First, the principle of intersubjectivity. It is not perfectly self-evident that one mind’s ability to know the truth value of a given proposition necessarily implies another mind’s ability to know the truth value of that same proposition. Experience testifies that some minds know things that other minds seem incapable of learning. The internal knowability of a truth does not seem, a priori, to justify an inference about the ability of various human minds to know it. This inference may be true, and our native democratic sympathy prompts us to regard it as probable, but its truth would have to be demonstrated. That is to say, while recourse to a principle of intersubjectivity may be a valid restriction to be placed on scientific pursuit, it is not a restriction either self-evident or weighted with the authority of a theorem. Therefore, whatever it is, it should not be regarded as an epistemological starting point or principle.
Second, the principle of verification is not obvious. That is to say, it is not self-evident that the only certainty available to the human mind is that which can be logically or empirically verified. It is not self-evident that the ability to verify the truth value of a proposition, whether by logic or empirically, is the only or distinguishing act of knowledge characterized by certainty. When Carnap says that the “only proper task of Philosophy is Logical Analysis,” this statement is not, in itself, an obvious proposition, a proposition known tautologically, the denial of which would violate the principle of contradiction. Thus, whatever it is, this alleged principle of verification cannot serve as an epistemological starting point or principle.
Thus, to conclude this first consideration, neither the principle of intersubjectivity nor the principle of verification is sufficiently self-evident to be regarded as an epistemological principle. This means that the valid application of these two alleged principles must itself be demonstrated ab extra. Their truth value must be established from outside of themselves. The propositional truth value of these two alleged principles must itself be subjected to a process of verification, either logical or empirical.
This brings me to my second consideration, namely, that neither the principle of intersubjectivity nor the principle of verification can be verified in either way. I can certify neither of these alleged principles empirically, because no empirical evidence testifies to them. My senses cannot demonstrate that I can trust only my senses, nor do my senses demonstrate that I can trust only the processes of logic, nor do my senses demonstrate that I can trust only my senses and my logic together.
Similarly, I cannot certify either of these two alleged principles logically, because neither one invokes a logical process. Logic does not prove to me that I can trust only the processes of logic, nor does logic prove that I can trust only the data conveyed by my senses, nor does logic prove that I can trust only my logic and my senses together.
That is to say, I cannot by logic know for certain that I can only know for certain what I know by logic. There is no law or process of logic that tells me this. Likewise, I cannot by logic know that I can know for certain only what I know empirically. There is no law or process of logic that tells me this.
Thus, to conclude this observation, neither the principle of subjectivity nor the principle of verification, nor the combination of the two, can be verified in either way or by both together. By the terms of Logical Positivism itself, therefore, it would appear that neither principle, nor both of them together, can supply what Logical Positivism calls cognitive meaning, since neither operative principle can be verified.
This double consideration brings me, then, to an answer to my first question: Are these two principles of Logical Positivism adequate? I must answer this question emphatically in the negative. If intersubjectivity and verification are to be regarded as the only two philosophical principles on which the scientific pursuit is to be based, science would seem to be burdened with an excessively restrictive epistemology. Left to themselves, these two principles appear to be inadequate to the proper pursuit of knowledge.
A Second Critical Question
This brings me to my second question: Are the principles of intersubjectivity and verification exclusive? Here there seems to be a very definite difference of opinion among scientists and philosophers of science. Two answers are given, yes and no.
Let us begin with yes. Among the Logical Positivists themselves, Carnap was the most explicit in asserting the exclusiveness of the principles of intersubjectivity and verification. If cognitive meaning, he argued, is limited to what can be verified, whether directly by logic or indirectly by empirical evidence, then other kinds of reflection cannot bear cognitive meaning. Foremost among these, he argued, is metaphysics, because metaphysical propositions are not verifiable in either of the two ways already mentioned. I quote a famous dictum from Carnap’s Philosophy and Logical Syntax:
What is most curious about this rejection of metaphysics, I believe, is its a priori character. Simply put, metaphysics is rejected for the simple reason that it is not physics. Indeed, according to Carnap, if the propositions of metaphysics could be verified, they would cease to be metaphysical and become physical! That position implies, obviously, that physics constitutes the limit of human knowledge. At this point it is difficult to perceive much difference between the Logical Positivism and the pure materialism of Thomas Hobbes, who taught that all the human mind can know are bodies moving in space.
There is a manifest difficulty in this materialistic thesis, however, demonstrating that the case for the Vienna Circle is really a circular argument. If physics is the only area of cognitive meaning, then all meaning is physical, including the very proposition that all meaning is physical. All thought is simply a physical exercise, which means that thought itself must follow physical laws. And since physical laws are determining laws, all knowledge is necessarily determined; therefore, there can be no certainty about the truth value of any proposition whatever, even the proposition that makes this assertion. I will return to this subject presently.
Before we leave the “yes” answer to our question, let me further remark that with the rejection of metaphysics as a source of cognitive meaning there necessarily follows the rejection of ethics and all propositions regarding value judgments. That quality of permanence, which the ancient and traditional philosophies perceived to be characteristic of metaphysical propositions, is reduced by Logical Positivism to what Carnap called “permanent emotional or volitional dispositions.” If so, this must also be true of ethics and value judgments; they must be rooted, not in the knowing mind, but in the emotions and the will. And since the only knowable reality is material reality, and since all matter is subject to entropy, how permanent will be these emotional or volitional dispositions to which Logical Positivism reduces metaphysics and ethics?
In summary, to enclose all knowable reality in a closed system is also to enclose the mind itself within that system and render it subject to the laws of that system. Clearly such a thesis removes all semantic reference from human thought and reduces it to a systemic solipsism. The Vienna Circle is reduced to a vicious circle.
Let us, then, look at the other possible answer to our question, “Are the principles of intersubjectivity and verification exclusive?” The second answer is no. There are other thinkers who believe that these principles, far from being exclusive, are to be used only as forming a kind of scientific protocol. Such an approach is that taken by Dr. Robert Pennock, in his book Tower of Babel: The Evidence Against the New Creationism. In it, he defends the use of these principles in science, he tells us, only as tools of the scientific discipline, not as general and exclusive principles of cognition.
Pennock makes this argument against Phillip Johnson, whom he accuses of confusing metaphysical naturalism with what Pennock describes as “methodological naturalism.” Johnson’s mistake, according to Pennock, is that he infers a dogmatic character in the present methodology of science, which is determined, as we have seen, by the application of the twin principles of intersubjectivity and verification. Johnson calls this process “dogmatic naturalism,” and he rejects it as epistemologically inadequate. This inference is unwarranted, says Pennock. Here are his own words:
Perhaps we should be glad for Dr. Pennock’s clarification of this point. By removing the note of dogmatism from science’s use of its hitherto restricted epistemology, he seems to have cleared the way for a much needed renewal of science by searching for a more ample assessment of cognitive meaning. Presently, nonetheless, I will show that Pennock’s theory is not so non-dogmatic as he claims.
A Modest Brief for Metaphysics
I propose that we endeavor to escape this closed epistemological circle through the trajectory known as metaphysics. Contrary to what that name is sometimes taken to suggest, metaphysics is not a cognitive pursuit that follows immediately upon physics. From earliest times, rather, it has been recognized that the beginning of metaphysics is not physics but the analysis of language. Thus, Socrates inquired of Euthyphron, “What do we mean by piety? . . . What do we mean by justice?” The correct approach to metaphysics is the abstract critical investigation of certain permanent concepts in our minds symbolized by our use of certain words.
The Logical Positivists, as we saw, already cut off the path to metaphysics by limiting cognitive meaning to what is logically or empirically verifiable, even though that limitation is not, itself, logically or empirically verifiable. As we have also seen, Pennock appears not to follow their example nor to seek their authority.
Yet, if we are to stick with Pennock, there is still a very large problem with our going to metaphysics from the analysis of language, because he too seems to eviscerate language of its potential for critical abstraction. For Pennock, as for so many authors in such disciplines as anthropology, sociology, and the philosophy of science, there would appear to be no characteristics in human language that distinguish it from the languages of other animals.
On the contrary, just as the contemporary random evolutionary theory, that espoused by Pennock, presumes an organic historical continuity between human beings and other biological forms, it also presumes a continuity of language. But if this is the case, the philosophy of language is inevitably burdened with the same epistemological restrictions as Logical Positivism’s philosophy of science. The Vienna Circle is transformed into a hamster’s wheel. Pennock’s “no” becomes the practical equivalent of Carnap’s “yes.” His soi-disant methodological naturalism takes on a decidedly dogmatic character, mocking his criticism of Phillip Johnson.
I do not know how Pennock could have expressed himself more clearly on this point. With respect to language he asserts, as though it were a brand-new discovery, something that mankind has in fact always known and often commented on. Namely, that animals convey messages by means of vocal sounds. Citing various published studies on the languages of chimpanzees, parrots, and other animals, Pennock boldly concludes: “Nor may we say any longer with assurance that we [human beings] are alone in our ability to communicate through language.”
I confess here to a certain wonderment about who in the world says such a thing, with or without assurance? On the contrary, no observant person will deny to animals their “ability to communicate through language.” The unexamined question here, however, the question about as subtle as a rumbling volcano, has to do with the content of that communication.
If I understand Pennock correctly, it is evidently sufficient that discourse among the beasts of the forest involves “what seems to be the rich emotional lives of animals.” He goes on to remark that “we may someday have to admit that animals have feelings of happiness and anger, playfulness and sadness, loss and even grief that are comparable to emotions that we ourselves feel.” Again, if I understand Pennock correctly, we still need more extensive studies (doubtless funded by generous academic grants) to inform us that animals convey a very wide range of emotions by means of sound. I submit that none of this information is revolutionary. Nor need it, I think, be tentative (“we may someday have to admit”).
One hates to insist on the obvious, but Pennock leaves us no choice. What is manifestly missing in his description of the vocal communication of animals is the slightest evidence of what philosophers call the a priori, the direct, intuitive perception of the permanent principles of thought, the capacity for abstraction through the processes of analogy, the spiritual awareness of transcendent noetic freedom.
When Pennock speaks of the “hitherto unappreciated conceptual and linguistic abilities” of animals, he does not include such fundamental perceptions as the Principle of Contradiction and abstract analogy, to say nothing of the Analogy of Being. Thus, not only can the beast render no critical assessment of the Ontological Argument, say, it has no access to such fairly simple notions as the specifying characteristic of primary numbers, the correct proportion of the diameter to the circumference of a circle, the analogue between a hypothetical syllogism and a constructive dilemma, the difference between a material implication and a material equivalence, or even the plain grammatical distinction, universally and abstractly considered, between a subject and a predicate. What animal other than the human being, I wonder, could have followed our earlier discussion, in these pages, of synthetic and analytical propositions?
Now, to be completely fair to him, Pennock does say these things tentatively. I quote: “Many of these investigations are still controversial, not in the least because of the tricky philosophical issues involved. . . .” I urge upon him, however, the consideration that there are no tricks involved here. The mind’s rise to abstraction, intentionality, universals, the perception of essence, and the derived principles of critical reflection is not tricky. A man can do it, and an animal cannot, but there is no trick to the thing at all. There is something in human language, and in the relationship of human language to human thought, that the animal does not know about, and can never know about.
The specifying characteristics of human language, some of which I have just listed, point to a radical, qualitative, insuperable discontinuity between human speech and the sound-communications of animals. These are the noetic experiences indicating that the human mind is not simply a part within a closed circular system. Indeed, it is also this very freedom of human thought—our ability to change our minds by an act of deliberate choice—that convinces us that we human beings ourselves are not simply the products of a random evolution determined by physical laws.
Now I admit that none of these considerations renders imperative the metaphysical pursuit. Indeed, I think of metaphysics as a gracious invitation, not an onerous injunction. For the sake of argument, moreover, I am not insisting here on the truth value of any particular metaphysical proposition. It is sufficient for my purposes that we are able to see that metaphysical questions themselves, whatever their answers, truly transcend both sense knowledge and logical process. It is sufficient that we perceive them to be questions whose permanent and native existence in our minds shakes a defiant fist against any closed, naturalistic interpretation of our life in this world. It is irrational to believe or presume that these very questions, which cast profound doubt on the thesis of a closed process, are themselves simply the continuation of a closed process.
Finally, let me confess that I do not regard even metaphysics as the complete answer to the higher aspirations of the human mind. On the contrary, in the back of all my comments on epistemology, there lies my conviction, as a Christian, that the radical attraction of metaphysics is really only a quiet manifestation of man’s yet higher call to theology. The enduring lure of metaphysics, I believe, is the mind’s innate response to the haunting presence of God’s Word and Holy Spirit in human consciousness. That said, it suffices here merely to indicate that the plain possibility of pursuing metaphysics summons us to escape the unjustified confinement of the Vienna Circle.
Letters Welcome: One of the reasons Touchstone exists is to encourage conversation among Christians, so we welcome letters responding to articles or raising matters of interest to our readers. However, because the space is limited, please keep your letters under 400 words. All letters may be edited for space and clarity when necessary. firstname.lastname@example.org
An introductory subscription (six copies for one year) is only $29.95.