Philosophy as Proto-Science
Where philosophy was, there science shall be.
My aim in this paper is to examine the structural and dynamic relationships between philosophy and science, particularly the view that philosophy anticipates and leads to science. My investigation sheds light on the nature of both philosophy and science.
Greek Origins of Occidental Philosophy as a Case Study
When seeking an explanation for the nature of philosophy, a good starting point is to inquire as to its origins. As we know, Occidental philosophy originated in Ancient Greece as an alternative to the mythological and religious answers that were then commonly given to relevant but unapproachable questions. Instead of accepting the usual explanations of the foundations and origins of reality based on the anthropomorphic projections of mythology, early Greek philosophers decided that the world could also be explained speculatively. They thus appealed to impersonal (or nearly impersonal) principles, for example, water (Thales), air (Anaximenes), fire (Heraclitus), infinity (Anaximander) and being (Parmenides), or life forces like love and hate or strife (Empedocles). Questions that could help us to understand the nature of philosophy are in this case: What was the reason for this change in explanatory approach? What was the nature of this change?
A good explanation for the shift from mythological to philosophical thought has been proposed by historians of philosophy. According to W. K. C. Guthrie, for example, Greek thinkers, having borrowed scientific knowledge (astronomical, physical, geometrical, arithmetical, etc.) from other cultures, were the first to consider such knowledge in abstraction from their practical applications, namely, in the form of theoretical generalizations. We find the best example of this outlook in Euclid’s Elements, with its axiomatic-deductive method of proving theorems. It was this awareness of the explanatory power of theoretical generalizations that presumably suggested to early Greek thinkers the possibility that questions once answered with the anthropomorphic metaphors of mythology and religion could instead be addressed in terms of abstract speculative generalizations, that is, in philosophical terms.
Although persuasive, this last explanation remains incomplete. True, the Greeks were the first to consider scientific generalizations apart from their applications. They were the first to axiomatize geometry, and they were able to make physical generalizations and astronomical inferences (such as, respectively, Archimedes’ measurement of specific gravity and Aristarchus’ heliocentric hypothesis). Nevertheless, to explain the rise of philosophical thought it is not enough to consider the emergence of explicit generalizations independently of their practical applications, for this is not a privilege of scientific explanation. Common-sense explanations, for example, are also based on empirical generalizations, like those expressed by sentences such as, ‘The sun rises everyday’, ‘Water quenches thirst’, ‘Fire burns’..., which are not scientific conclusions, but have always been accepted as obviously true. Moreover, people have certainly always been able to think about such commonplace generalizations apart from practical concerns.
A more complete explanation for the emergence of philosophy in ancient Greece seems to me to be the following. When they succeeded in creating abstract scientific knowledge, Greek thinkers, from Thales to Aristotle, also achieved an intuitive understanding of the nature of the generalizations and explanations of science, both of the formal sciences (geometrical theorems) and the empirical ones (physical and astronomical laws). While they did not have an explicit philosophy of science from the start (the first steps in this direction were taken later by Aristotle in his Organon, mainly in the Posterior Analytics), they certainly did have an idea of the kind of hypothetical, predictive and explanatory procedures that are in a broad way shared by the sciences in general – both empirical and formal. Thus, they already had what we could call an idea of science. Now, it seems that Greek philosophy arose from the speculative application of this idea of science to questions that earlier were approached exclusively by means of religion and mythology, like the question of the ultimate nature of the world and of our place in it. Equipped with this new notion, early Greek philosophers attempted to proceed rationally, first by seeking to establish true generalizations based on certain kinds of data (empirical or formal), and then by trying to explain certain kinds of facts, whatever their nature, by applying these generalizations. The first Greek philosophers pursued this aim by introducing vague principles (like water, air, infinity, being) or forces (like heat and cold, love and strife). These might be interpreted as the first attempts to replace explanations relying on the actions and intentions of divinities with explanations based on the constitutive elements of the real world and the impersonal laws regulating their transformations, often hovering midway between the two kinds of explanation. It was by no means accidental that Thales, the first philosopher of the Occidental tradition, was also a natural scientist and a competent astronomer who once predicted a solar eclipse.
Philosophy as Conjectural Inquiry Lacking Consensual Foundations
If we accept it as given that Occidental philosophy developed through the speculative application of the idea of science to questions inherited from mythology and religion, how can we then distinguish the activities of philosophers from those of scientists? Despite some suggestions to the contrary, there seem to be considerable differences between them. The answer to this question brings us to what I regard as a central insight into the nature of philosophy. Even if philosophical methods generally resemble the practices of scientific inquiry, there is a fundamental difference between them, namely, that philosophical explanations remain merely conjectural and, to this extent, speculative.
But what do the words ‘conjectural’ and ‘speculative’ mean when we say that philosophical investigation remains conjectural or speculative? One answer is that an investigation is conjectural if it produces only hypothetical results, and that this is the case when there is no possibility of consensual agreement about the truth of these results. Indeed, while it is rather easy to reach consensual agreement on results in the sciences, this kind of consensus is impossible in the murky waters of philosophical inquiry. Consider the difference: The Greek scientist Archimedes explained how levers work by precisely formulating the law of the lever, and his explanation could be empirically verified and agreed on by everyone. In contrast, the pre-Socratic philosopher Empedocles proposed to explain the creation and destruction of things in the world through the action of the forces of love (eros) and strife (neíkos) on the four elements (water, air, earth and fire), which was nothing more than vague, obscure speculation. He developed this theory in a mode and domain of inquiry where thinkers were unable to find a viable path to consensual agreement.
The conjectural character of philosophical thought – as the result of a lack of consensual agreement on fundamental matters – reveals itself to be a necessary property able to explain its typically argumentative and aporetic character. For when thinking cannot be other than conjectural, there is no alternative except to embark on hypothetical reasoning: We begin by accepting certain non-consensual assumptions and then apply our best knowledge and skills in order to find all their implications. Then we (usually other philosophers do this) change the assumptions and proceed in a similar way. We subsequently try to critically compare the different results and the procedures that lead to them, in a process that can be endlessly repeated. In this way, philosophers are always beginning: they are always pondering new ideas in ways that usually generate aporetic argumentative discussion.
The conjectural character of philosophical inquiry also suggests an explanation for the lack of progress in philosophy: since philosophers cannot achieve agreement on the truth of their ideas, inter-theoretical comparisons must remain inconclusive. Thus, to give an example, scientists would generally agree that Einstein’s relativistic mechanics is superior to Newtonian mechanics, since the explanatory power of the former is greater – this is a matter of scientific conclusions. On the other hand, philosophers have remained divided on alternative explanations of many important issues. Consider, for example, the disputes over the problem of universals, the mind-body problem, the free-will problem…).
Still, why can’t we achieve consensual agreement on the results of the philosophical endeavour? The answer is that consensual agreement about the results of an investigation is only possible when there is sufficient agreement about the main presuppositions underlying the investigation. Previous agreement on these matters is always absent from philosophical inquiry. Philosophy lacks:
(i) agreement about the adequacy of its data, general principles and even problems (philosophical ‘data’ and principles are uncertain, and there are philosophical questions, we suspect, which are pseudo-problems resulting from linguistic-conceptual confusion);
And it also lacks:
(ii) agreement on the adequacy of its methodological procedures for evaluating the truth of answers proposed for philosophical questions (an argument or a set of arguments can appear conclusive to one philosopher, but unpersuasive to another).
In opposition to this, conditions (i) and (ii) are always sufficiently satisfied in the case of scientific research. Scientific problems and procedures are relatively uncontroversial, and the correct solutions, when finally found, can be publicly verified, if not with certainty, with a high degree of probability. Indeed, where fundamental preconditions like these cannot be satisfied, there is no way to achieve consensual agreement concerning the truth (or probable truth) of the conclusions, which means that we cannot escape the aporetic discussions typical of philosophy.
Philosophy as Proto-Science
The foregoing discussion suggests that by investigating the similarities and contrasts between philosophy and science, we will be better able to explain some central features of philosophical inquiry. Moreover, they invite us to ask if our present philosophical inquiries will someday be absorbed into science when they achieve a degree of maturity that allows practitioners to reach consensual conclusions. In other words: Could philosophy be seen as a conjectural inquiry anticipating science – a proto-science? Could all philosophical inquiry be seen in this way?
We are not in the position to assert this. But an affirmative answer to this question is suggested by the historical fact that most of the sciences grew out of philosophical inquiry. Consider a few examples from several different scientific fields:
A. According to Karl Popper, the now accepted astronomical understanding that the Earth is a large, round body moving in empty space, impelled by inertial and gravitational forces, was already anticipated by Anaximander (610-546/5 BC). This Greek philosopher proposed that the Earth was a stationary cylinder, not held in place by anything else, but floating unsupported in space because it is equally distant from everything in the universe, and it is impossible for it to move simultaneously in opposite directions.
B. The scientific investigation of subatomic particles by contemporary physics has its forerunner in the speculative hypothesis of the atomistic philosophers, from Democritus to Epicurus, that visible things are formed by the aggregation of extended invisible (because extremely small) but physically indivisible particles.
C. Biological theories of evolution seem to be dimly anticipated by Anaximander’s insight that since man is helpless as a child he would have perished in primeval times if he were not descended from creatures very much like wild animals…
D. The Platonic theory of the tripartite soul has its modern counterpart in Freud’s structural theory of mind, which divides the mind into the I (ich), the it (es) and the over-I (über-ich) (commonly referred to as ego, id and super-ego). It is true that psychoanalysis strongly resembles philosophy, insofar as its practitioners are still unable to reach consensual agreement on many issues, but it had in Freud’s hands a relatively controlled method used as a form of investigation.
E. Wittgenstein’s therapeutic conception of language as a nebula of language games working as unities of meaning anticipated the much more systematic (and narrower) theories of speech acts of J. L. Austin and J. R. Searle, which nowadays belongs more to linguistics than to philosophy.
These are only a few examples, and the developmental process is continuing. Many believe, for example, that once we really understand how the brain works, many of the riddles of our present philosophy of mind will yield to consensual (and in this sense scientific) solutions. All these facts lead us to ask whether science might not someday replace the remaining central philosophical fields, such as epistemology, metaphysics and ethics.
Nevertheless, there are philosophers who resist the notion of philosophy as proto-science. Echoing Wittgenstein, Anthony Kenny holds that philosophy, unlike science, deals with knowledge as a whole, since it aims to organize the already known, providing an overview of our knowledge. This kind of comprehensiveness, he argues, is absent in the particular sciences. Consequently, at least central areas of philosophy such as metaphysics, epistemology, the theory of meaning and ethics will forever remain philosophical.
Nonetheless, some overview and some degree of comprehensiveness can also be achieved by scientific inquiry. Why could a wider overview not be scientific? I suspect that the main reason for the resistance lies less in the nature of things than in outdated positions on the nature of science that are still uncritically accepted by many philosophers. Indeed, these opinions, which have their roots in the philosophy of natural science developed by the positivists – and also in the main reactions against them –, are often too restrictive to assure that our central philosophical interests will receive their deserved place in some future scientific inquiry. If applied, they would be impoverishing, destroying philosophy in its kern.
Consider, for example, Popper’s conception of science as an inquiry that aims to construct theories that can resist falsification by decisive experiments. This view is too restrictive, for it seems to exclude the theory of biological evolution from science, since the former is not decisively falsifiable: How would we conceive of an experiment capable of falsifying a hypothesis about an evolutionary process that occurred in the distant past? Given this problem, how could we ever apply a standard as restrictive as falsifiability (which arguably may be applicable to physics) to the central subject areas of philosophical inquiry, such as epistemology, metaphysics and ethics, other than in a crassly reductive or even eliminative way?
Indeed, if we accept such a view of science, our attempt to conceive of philosophy as proto-science would have to end here. The reason for this pessimistic conclusion is that when our view of the nature of science is inspired by the investigation of a well-established particular science like physics, we are led almost perforce to reductive generalizations about the character of still unknown areas of science. What we are looking for is a concept of science so general and inclusive that any new investigation deserving the name of science that might chance to emerge could satisfy it, for it is credible to imagine that this would be precisely the concept of science that could be properly contrasted with that of philosophy.
The Right Contrasting View of Science
To arrive at this more balanced view of science, I propose that we should not adopt a model settled on by some already established science, but rather should rely on scientifically informed common sense. We must begin with questions such as: What does the scientific community as a whole understand as ‘science’? How would scientists recognize any new theory or field of investigation as belonging to science? When considering these questions, the obvious answer that occurred to me was that science should be systematically contrasted with philosophy in the sense that science is not conjectural: It achieves consensual agreement on its results because it has already achieved consensual agreement concerning basic issues such as data, general principles and methodological procedures.
Searching in the literature, I found that such a balanced view of science was already suggested by John Ziman, who understood science in general as ‘consensualizable public knowledge’, that is, as any kind of knowledge susceptible to consensual agreement about its truths. According to this perspective, science is essentially constituted by generalizations that are – or at least are able to be – consensually accepted as true by the members of a scientific community.
Ziman’s notion of science is in complete accord with the picture most informed laymen and scientists have of science. When we talk about the progress of science, we are thinking of the acquisition of new knowledge that the community of specialists can or could evaluate with certainty and precision. This view of science is also sufficiently general and flexible to include everything we usually accept as belonging to the sciences, both the empirical and the formal. Moreover, placing the concept of consensual agreement at the centre of attention, this view of science seems to provide the ideal contrast between philosophy and science, since, as we have seen, the first is an inquiry identifiable by a lack of possible consensual agreement concerning its results. Accordingly, even if philosophy, as Kenny thought, should be a comprehensive inquiry aiming to achieve an overview, it could also be proto-scientific, insofar as we cannot rule out in advance the possibility that over time philosophical theories could become a sort of consensualizable and comprehensive public knowledge.
However, isn’t the definition of science as ‘consensualizable public knowledge’ too inclusive? It might seem to be, because there are ideological circumstances in which ‘consensus’ is imposed from above, excluding the possibility of critical evaluation. Notorious examples of this are the roles played by political ideologies in defining legitimate science in Nazi Germany (excluding non-Aryan science) and the Soviet Union (excluding non-Marxist biology) and the religious ideology of the Catholic Church that established Geocentrism (and condemned Galileu as heretical). Yet, in accord with the above characterization, such ideological impositions do seem to pertain to science, since a scientific community of ideas has consensually accepted them. Thus, as presented, the proposed characterization of science seems incapable of distinguishing science from an ideological by-product.
Nonetheless, we can regard this difficulty as only apparent, if we distinguish between authentic and inauthentic consensus, specifying what we understand as a community of ideas that is able to produce science in a way that excludes inauthentic consensus. Keeping the contrast with philosophy in mind, I suggest we call a community able to warrant authentic consensus a critical community of ideas, understanding it as a community that satisfies some constitutive conditions approximating those specified by Jürgen Habermas for what he calls an ideal speech situation (ideale Sprachsituation). This means that we must define a critical community of ideas as something that satisfies constitutive conditions warranting the claim to authentic consensus. Without trying to be either systematic or exhaustive, I propose that we can generally characterize the main constitutive conditions for a critical community of ideas as requiring:
(a) Commitment to seeking truth: The members of the community should seek to find truth throughout the entire process of inquiry and evaluation of ideas.
(b) Freedom of discussion: There must be an equal opportunity for free critical discussion among the members of the community of ideas; they should not be subject to any intellectual constraints, except those of the best arguments.
(c) Full access to information: All members of the community must have full access to information and equal chances for the evaluation and exchange of ideas.
(d) Shared competence: All members must have suitable training in order to be able to make adequate evaluations regarding their fields of research.
Indeed, Nazi Germany’s Aryan science and the Soviet Union’s Marxist biology only prevailed because their scientific communities did not satisfy such conditions. A truly scientific consensus can only be produced by sufficiently satisfying constitutive conditions like these, which make possible free and rational evaluations of the results of scientific investigation. When we evaluate reports of a new scientific discovery, we always assume at least that the scientific community has satisfied the conditions of commitment to seeking truth, free discussion, full access to information, and shared competence, if not in full, at least to a sufficient degree.
Another important objection that critics could make against such a consensus-based view of science is that it would be too dependent on social consensus, compromising its objectivity. It seems at first glance that science can be whatever the critical community of ideas decides to call science, arbitrarily disregarding objective criteria. However, this is not how science is defined in practice. For the critical community of ideas aims at achieving a consensus about truth, and as a matter of fact it is unable to achieve this aim in arbitrary ways like consulting crystal balls and similar superstitious practices. It is simply a matter of fact that a critical community of ideas must fulfil the appropriate objectivity conditions for a chosen epistemic domain if its aim is to achieve consensus about truth. In other words: Experience has shown that no community of ideas ever achieves an authentic consensus about truth unless it first meets some appropriate conditions for objective evaluative consensus. Indeed, without attempting to be either systematic or exhaustive, we can show that this is the case by making a list of conditions that must be sufficiently satisfied by any critical community of ideas able to reach an objective consensus about how to achieve truth. These conditions are what we could call conditions of scientific objectivity. Indeed, in order to achieve objective consensus there must at least be previous agreement about:
(i) what should be counted as the (empirical or formal) basic data and/or general principles of the epistemic domain to which certain scientific theories should be applied;
(ii) what can be accepted as adequately formulated questions to be asked concerning the epistemic domain (theories must answer meaningful questions);
(iii) what can be accepted as an adequately constructed theory in the epistemic domain (i.e., adequate in its internal, as well as in its external coherence within a wider conceptual framework);
(iv) what can be accepted as the procedures of truth-evaluation in a theory’s epistemic domain (which should involve some kind of correspondence between a theory and the facts the theory is meant to explain, together with the accepted forms of verification procedures for finding this correspondence, etc.).
Such conditions of scientific objectivity are different to each scientific field. But they must be satisfied in order to assure the factual truth of scientific work, and they coincide in many ways with the kinds of things that philosophers of science often investigate in depth with regard to their preferred scientific field. The difference is that these philosophers have too often considered only such conditions and their particularized ramifications, abstracting the social role of the critical community of ideas. On the contrary, we regard the satisfaction of such conditions only as an indispensable prerequisite for the successful scientific functioning of a critical community of ideas. As already noted, even if these conditions are not met a priori, the need for their satisfaction in order to achieve consensus on truth is an inescapable matter of fact, learned through experience by any community of ideas effectively committed to the achievement of truth.
With the aid of these notions, we can improve Ziman’s general characterization of science as ‘consensualizable public knowledge’. Here is our understanding of science:
SCIENCE = a body of non-trivial generalizations reached by the members of a critical community of ideas (the community of scientists), these generalizations (sometimes seen as scientific laws) being (or being able to be) consensually held as true by this community.
This is a better understanding of science. It is better in the sense that it is unbiased, according sufficiently with the view of science that everyone, from scientists to the educated public, generally holds. And it is also better, because it cannot be seen as reductionist or positivist: Any discipline that well-informed, objective evaluators deem a science should be compatible with this characterization, for the first requirement of the scientific enterprise is the possibility of agreement on the truth-searching conditions of non-trivial generalizations shared by the members of a critical community of scientists.
Right View of Philosophy Contrasted with Science
The above-outlined consensualist-but-objectivist view of science enables us to establish the appropriate relation between science and philosophy. We can oppose the consensualizable public inquiry of science with the non-consensualizable conjectural inquiry of philosophy. In order to achieve this, we can characterize philosophy as follows:
PHILOSOPHY = a conjectural body of non-trivial generalizations arrived at by the members of a critical community of ideas (the community of philosophers), without this community being able to reach any consensual agreement on the truth of these generalizations.
In accord with this characterization, we can regard any conjectural inquiry in any domain of thought where it is impossible to achieve a consensual body of truths to be of a philosophical nature. Its philosophical nature results from its failure to satisfy the truth-searching conditions that can make consensual agreement in the critical community of ideas possible. In short: philosophy lacks (i) agreement about its basic data and/or principles, (ii) agreement about the right questions to pose, (iii) agreement about the right form of its theories, and (iv) agreement about the right procedures for its truth-evaluation.
Indeed, in those difficult domains where science, understood as ‘consensualizable public knowledge’, clearly remains impossible, only the conjectural inquiry of philosophy is available. In this way, we can explain why philosophy, in conformity with the etymology of the word, is the love (philo) of knowledge or wisdom (sophia) and not the attainment of knowledge (scientia). In the words of Bertrand Russell: ‘Science is what we know; philosophy is what we don’t know’… ‘Science is what we can prove to be true; philosophy is what we can’t prove to be false’. Indeed, when philosophy achieves consensual truth, it ceases to be philosophy and becomes science. Even the meta-philosophical understanding I am outlining in this paper could be accepted as belonging to science, if the critical community of ideas were able to achieve authentic consensus on its truth.
Another point that we should note is that the practice of philosophy always presupposes a critical community of ideas, even if in some cases (like those of Vico, Peirce and Nietzsche) in a counterfactual sense. A well-known criticism of medieval philosophy is that by accepting Christian dogmatism as above criticism, it fell short of satisfying this condition.
Finally, one could object that as a typically ‘higher-order’ form of investigation, by its very nature philosophical inquiry is not subject to objective verification and, consequently, to the kind of objectively grounded consensus achieved by science. Our response is that this argument may well be overly pessimistic. The main reason to think so is that support for much theoretical work is not just directly empirical – through observational verification – but also inter-theoretical. We can often find this kind of support in the sciences. Take as an example the Darwinian theory of evolution. Darwin and his contemporaries developed their ideas without recourse to genetics, since Mendel’s work was unknown to early evolutionary theorists. Nevertheless, the subsequent rediscovery of genetic theory by the scientific community provided extremely important inter-theoretical support for evolutionary theory. Something similar can also occur within ‘higher-order’ philosophical inquiry.
It was once figuratively suggested that the problems of philosophy are so intertwined that any one problem can only be solved when all the other problems have already been solved (Wittgenstein). Far from being pessimistic, this thesis points to inter-theoretical support. Insofar as related fields of knowledge move toward science, this provides new inter-theoretical support for philosophical insights, paving the way for consensual scientific knowledge.
Proto-scientific versus analytic-conceptual views
Once we accept these proposals, we see that the supposedly essential differences in subject matter or even in methods between philosophy and science are illusory. Take, for example, the still widely believed conception according to which philosophy is a non-empirical, higher-order activity of conceptual analysis (its method) intended to make explicit the structure of our most central concepts and the relations between them (its subject matter). This view or something alike arose due to the prominence of the philosophy of language in the first half of the Twentieth Century. In the second half of the Twentieth Century, however, the philosophy of language lost its status as the most productive philosophical field to the philosophy of mind, which consists largely of empirical speculation.
Moreover, the fact that a given form of philosophical inquiry has a linguistic-conceptual character does not mean it cannot develop into a science. This is exemplified by J. L. Austin’s theory of illocutionary forces. As he himself foresaw, today this theory belongs, in the form of the theory of speech acts, more to the scientific field of linguistic than to philosophy. The reason for this is that it has achieved enough consensual agreement to lose its more plastic role in the uncertain domain of conjectural thought. Hence, there seems to be no contradiction between understanding philosophy as proto-science and understanding it as conceptual analysis, since the latter can be regarded as belonging to the former.
Finally, we can offer a meta-philosophical refutation of the thesis that the proper object of philosophy is of a conceptual nature. As W. V. Quine rightly noted, philosophers often need a particular resource that he called a semantic ascent. A semantic ascent could also be called a semantic meta-language (a semantic meta-language is different from a syntactic meta-language: whereas the latter has as its objects signs and their relationships, the former also has as its objects meanings, and with them, indirectly, the world as we mean it; in Rudolf Carnap’s simplified example, instead of saying, ‘Five is not a thing but a number’, the philosopher prefers to say, ‘“Five” is not a thing-word, but a number-word’.) However, the call for semantic ascent need not be confusing, for this is nothing more than a propaedeutic resource, aiming at the achievement of the kind of conceptual rigor usually demanded by philosophical arguments. Even if philosophers like Carnap have seen here a proof that the object of philosophy should be purely linguistic-conceptual, this cannot be true, as Quine realized, because every sentence of the empirical sciences can also be meta-linguistically represented in this way. As he noted:
“There are wombats in Tasmania” might be paraphrased as ‘‘Wombats’ is true to some creatures of Tasmania’, if there were any point in it; but it does happen that semantic accent is more useful in philosophical connections.
The upshot of this argument is that philosophy does not have concepts (e.g., meaning, knowledge, consciousness, substance...) as its proper subject matter, any more than does science (e.g., genes, molecules or superstrings), except for reasons of semantic ascent. We can regard the task of both a theoretical physicist and a philosopher of mind, for example, as not only to analyse and combine concepts, but also to work toward solving empirical questions, the latter in much more speculative ways. Hence, all that we can intend by saying that philosophy is conceptual analysis is to refer to certain methodological resources, not to an indispensable approach, and still less to its proper subject matter.
To the question of whether all philosophy might be an anticipation of science, assuming the wide concept of science that we have proposed, the only answer is that we have no strong reason to think otherwise. Moreover, it makes sense to accept this as at least a normative assumption, since it gives us a ground to progress toward truth.
More Complete Framework
While I have limited myself here to the relationship between philosophy and science, I think that this is only one aspect of a more complete framework that places philosophy within a wider perspective. In my book on the nature of philosophy, I explored to some extent this wider perspective, conceiving philosophy in general as a derivative cultural activity. Opera, for example, is an artistic activity combining plot, poetry and music. In this regard, philosophy has some similarity to opera. It seems to be a kind of amalgam of motivations, materials and procedures borrowed from three fundamental cultural activities: art, religion, and science. These cultural activities can be represented as forming the corners of a triangle, inside of which the various philosophical activities find their places. The scientific corner of the triangle is responsible for the solid, practical, reality-bounded and truth-oriented aspects of philosophy. The mystical-religious corner is responsible for the speculative-transcendental, verbally inexpressible element, usually grounding the comprehensiveness of philosophy, the traditional breadth of the philosophical quest in its inquiry about the world as a whole and man’s place in it. The aesthetic-artistic corner, finally, is responsible for the metaphorical dimension that to different degrees is always unavoidably present in philosophical discourse. We can use this scheme to classify the various forms of philosophy. We can locate them in different positions inside the triangle. At its centre, we can locate philosophies that in a balanced manner have scientific (truth-oriented), religious (transcendental) and aesthetic (metaphorical) dimensions. Examples are Plato’s Republic, Descartes’ Meditations, and Wittgenstein’s Tractatus. However, there are forms of philosophy located near the scientific corner of the triangle, like Carnap’s Logical Grammar of Language, Quine’s Word and Object and Austin’s How to Do Things with Words. There are works near the mystic-religious corner, like John Scotus’ On the Divisions of Nature and Meister Eckhart’s treatises. Moreover, there are those near the aesthetic corner, works by poet-philosophers, like Nietzsche’s Zarathustra and (almost crossing the border) Novalis’ Hymns to the Night. And there are also works near to some side of the triangle, like Heidegger’s writings, which can be placed near the aesthetic-religious side...
We can also use the triangular diagram to classify entire cultural traditions linking philosophy with a corner of the triangle. These are the cases of the scientifically-oriented English tradition, the mystically-oriented German tradition and the belletristically-oriented French tradition.
Finally, the relationship between the components is not stable: it is possible to perceive in the sub-domains a wide, gradual movement from the aesthetic-mystical side of the triangle to the scientific corner, as an inevitable consequence of the continuous and now accelerating advancement of science.
 Similar principles have continually been proposed over the entire history of philosophy: Plato’s ideas, Aristotle’s substance, Plotinus’ Uno, Aquinas’ God, Kant’s noumena, Fichte’s I, Hegel’s Absolute, Schopenhauer’s Will, Heidegger’s Being and Wittgenstein’s unsayable, played a similar foundational role.
 See Guthrie, W. K. C., A History of Greek Philosophy (Cambridge: Cambridge University Press, 1962), vol. 1, pp. 36 f.
 A similar procedure is even used by philosophy understood as conceptual analysis: philosophers usually consider certain data, such as those found in examples, paradigmatic cases, thought-experiments, etc., in an effort to find conceptual generalizations adequate to explain a broad set of conceptual applications.
 This phenomenon was already identified by Auguste Comte, when he considered what he understood as the transition from mythological to metaphysical thought. For a discussion, see Claudio Costa, The Philosophical Inquiry: Towards a Global Account (Lanham, MD: University Press of America, 2002), chap. 4.
 According to Hegel, Oriental philosophy never distinguished itself enough from religion; the reason could be that they also never had in sight a sufficiently clear model of science and systematic scientific procedures.
 For a proposal to the contrary, see W. V. Quine, ‘A Letter to Mr. Osterman’, in C. J. Bontempo & S. J. Odell (eds.), The Owl of Minerva (New York: Free Press, 1975). Quine suggests that the boundaries between philosophy and science are arbitrary, like those between different jurisdictions demarcated on a map. If this were true, agreement about whether new ideas belong more to philosophy or to science would have to be settled by establishing conventions. But this is not what actually happens in practice. Usually such agreements arise naturally and immediately.
 In some passages, Ludwig Wittgenstein defended the thesis that philosophy is not constituted by argumentative theoretical conjectures, but is rather a therapeutic activity of describing how language really works able to dissolve them as pseudo-problems. See Wittgenstein, Philosophische Untersuchungen (Frankfurt: Suhrkamp, 1983), sec. 109. However, as many critics have remarked, neither Wittgenstein nor his followers have come even remotely close to achieving this aim; for the obscurity and elusiveness of Wittgenstein’s arguments do not transform them into descriptions. See A. J. Ayer, Wittgenstein (New York: Pelican Books, 1985), p. 137.
 K. R. Popper, ‘Back to the Pre-Socratics’, in his Conjectures and Refutations (London: Routledge, 1962), p. 138.
 Anthony Kenny, Aquinas on Mind, (London: Routledge, 1993), p. 9.
 See K. R. Popper, Conjectures and Refutations, pp. 339-340.
 This is the general thesis on the nature of science defended by J. M. Ziman in Public Knowledge: An Essay Concerning the Social Dimension of Science (New York: Cambridge University Press, 1968), chap. 2. See also H. L. Longino, The Fate of Knowledge (Princeton, NJ: Princeton University Press, 2002).
 I add the words ‘are able to be’ because there are many scientific hypotheses that we still do not know how to prove or disprove, although we have good reasons to believe that we will eventually be able to test them. Maybe the best known example of this is superstring theory in physics.
 See Jürgen Habermas, ‘Wahrheitstheorien’, in Vorstudien und Ergänzungen zur Theorie des Kommunikativen Handelns (Frankfurt: Suhrkamp, 1984), pp. 174 f.
 Quotes taken from Allan Wood’s postscript to Bertrand Russell’s My Philosophical Development (London: Routledge, 2004).
 One could also object that the proposed characterization is overly inclusive: There are some theories, e.g., Freudian psychoanalysis and Marxian dialectical materialism, which are not considered to be typically philosophical, even though they lack consensual agreement about their results. I think that the problem here is in part just one of nomenclature, for Freudianism and Marxism are in fact quite philosophical.
 The persistence of this view is underlined by the essays of Robert Brandom, Barry Stroud, Allen Wood and Karl-Otto Apel, published by C. P. Ragland & S. Reidt in What is Philosophy? (New Haven: Yale University Press, 2001). For standard presentations of similar views, see Michael Dummett, ‘Can Analytical Philosophy be Systematic and Ought it to Be?’ in his Truth and Other Enigmas (London: Duckworth, 1978), and Ernst Tugendhat ‘Überlegungen über die Methode der Philosophie aus Analytischer Sicht’, in Philosophische Aufsätze (Frankfurt: Suhrkamp, 1992).
 Also J. L. Austin saw no contradiction between philosophy as proto-science and philosophical analysis, since, on the one hand, he championed philosophy as conceptual analysis and, on the other hand, he was an energetic defender of the here-developed view. See the often-quoted passage in ‘A Plea for Excuses’, in his Philosophical Papers (Oxford: Oxford University Press, 1961), p. 232.
 W. V. Quine, Word and Object (Cambridge, MA: MIT Press, 1960), p. 270 f. See also Claudio Costa, The Philosophical Inquiry, pp. 15 f.
 W. V. Quine, Word and Object, pp. 271-272.
 There are many other problems that cannot be dealt with here. For example, how would we locate certain non-central domains, like those of the philosophy of existence, philosophy of life, or the critique of culture – which have changeable subjects – in our scheme? (Probably in ways similar to those in which the historical sciences can be seen as consensualizable). Another point is that the development of science can itself create a room for new and previously unforeseen philosophical fields. Consider, for example, the philosophy of computational science.
 Claudio Costa, The Philosophical Inquiry: Towards a Global Account, chaps. 4-6.