Discussions within the philosophy of science oftentimes refer to the Received View and the criticisms this view has generated. It was called the "Received View" because there was a great deal of consensus on it prior to the 1960s. What is this view?
Simply put, the Received View refers to the attempt by philosophers of science to construe scientific theories as axiomatic calculi which are then given a partial observational interpretation by correspondence rules linking theoretical terms to sets of observations. This view dominated the philosophy of science from the 1920s all the way through the 1950s, after which a number of criticisms developed that effectively brought the theory to its knees. What is the background of such a view?
The Received View grew out of the school of Logical Positivism, but survived the demise the latter. In order to understand the Received View, it is therefore quite helpful to know something about Logical Positivism.
The origins of Logical Positivism can be traced to Hans Reichenbach's "Berlin School" and to the philosophy of the Vienna School. As a movement, Logical Positivism rejected traditional metaphysics, concerning itself instead with foundational issues in science. It had its origins within the German universities and rested oftentimes upon the power and authority of individual professors.
Ludwig Büchner's mechanistic naturalism from roughly the 1850s to the 1880s can be seen as an important source for Logical Positivism. Rejecting any a priori elements in science, Büchner held that we have an immediate empirical knowledge of the laws of the natural world that govern the movement of matter.
During the 1880s and 1890s, Helmholtz, Cohen and the Marburg School of Neo-Kantianism generally claimed that webs of a priori logical relations are exemplified in the external world and that it is the aim of science to discover the general structure of sensations.
At about the same time, Ernst Mach was also arguing that there is no a priori which organizes the facts of science, but rather that science is a conceptual reflection upon the givenness of facts. He famously rejected that neither space nor time is absolute and claimed that ultimately all empirical statements comprising scientific theory must be reducible to statements about sensations.
Thus it is that by 1900 the following schools of thought held sway, all contributing to Logical Positivism, and all of which were challenged by the theory of relativity and quantum theory generally:
- Mechanistic Materialism with its roots in Büchner's thought;
- Neo-Kantianism and its claim of the a priori nature of logical relations;
- Machian Positivism rejecting the a priori.
The Vienna Circle and Reichenbach's Berlin School both sought a philosophy of science that was compatible with the new physics. Both believe that Mach's verifiability criterion of meaningfulness was essentially correct: Putative scientific claims that could neither empirically confirmed nor disconfirmed were meaningless. Simply put, scientific statements required truth conditions as the sine qua non of meaningfulness. Both schools also believed that mathematics was very important in science, accepting along the way Poincare's thesis that one ought understand scientific law in terms of conventions about how one might talk about phenomena. Accordingly, both supposed that the subject matter of theories are phenomenal regularities and that these regularities can be characterized by theoretical terms. Both claimed that while theoretical terms are mere conventions used to refer to phenomena, the same assertions made employing these theoretical terms could in principle be made within phenomenal language generally, i.e., explicit definitions of theoretical terms were possible in this way.
The original Received View was heavily influenced by the mathematical logic of Frege and Cantor, as well as the work of Russell and Whitehead. In the early days, the logical axiomization of theories was particularly important with correspondence rules granting an observational interpretation of theoretical propositions.
Logical axiomization proceeds by using logical and mathematical terms both to formulate scientific laws and specify the relationship among theoretical terms which themselves are construed as abbreviations of phenomenal descriptions. Observational terms, on the other hand, are given an explicit phenomenal interpretation. Correspondence rules are employed to give explicit definitions to theoretical terms and consisted in biconditionals. Thus, for all x, x has theoretical property T if and only if x has observational properties O. The idea here is that all theoretical terms could be correlated with congeries of observational terms.
The aim of the approach was always to eschew metaphysics. Since for all x, x has T just in case x has O, one does not need to grant some non-empirical ontological status to theoretical entities. The existence of these biconditional "bridge rules" giving an observational meaning to theoretical terms meant that no supersensible or nonsensible entities need exist, a happy event for anyone wanting to limit the metaphysical within science. The verificationist criterion claiming that the meaning of a term is its method of verification also effectively precluded any appeal to the metaphysical. There was a general concern to construct a logically perfect language that would make no reference to metaphysical entities.
Since all assertions of scientific theory are in principle reducible to assertions about phenomena in the observational language, all assertions of scientific fact are reducible to assertions in a basic phenomenal language. Theorists called this language a protocol language directly referring to the givenness of observational experience. Within this protocol language, one could distinguish particular assertions from generalizations.
But storm clouds were gathering on the horizon. Granted that we have a protocol language, what precisely is this language about? One group claimed that the language referred to incorrigible sense data. The problem with this, is that such sense data appears to be subjective. The incorrigibility of immediate experience carries with it subjectivity. Another group claimed that we must eschew subjectivity and that we can only do that by allowing the protocol language to refer to physical things and their properties. Now the problem of subjectivity has been fixed, but our experience is no longer incorrigible. Thus it is that there was both a phenomenalist and a physicalist interpretation of the protocol language, the first emphasizing incorrigibility but losing objectivity, and the second emphasizing objectivity but losing incorrigibility. In what then could the givenness of experience consist?
There were other problems as well. As is well-known, all inductive arguments are invalid, i.e., it is always possible for the premises of such arguments to be true, while their conclusions are false. The problem is that no matter how many times there is a correlation among our empirical experiences, it is always logically possible that the next experience will be one in which that correlation does not hold. This "problem of induction" is often called Hume's problem, after the 18th century Scottish philosopher, David Hume.
Within the philosophy of science, the problem of induction seems to collide with the axiomatic and deductive nature of scientific theory. While there were attempts to formulate an inductive logic with clear algorithms, on empirical grounds one cannot observe a generalization, and, moreover, it is always logically possible that one's next experience will disconfirm the generalization under consideration.
Overwhelmingly important in the Received View is the notion of a correspondence rule. Sometimes called "rules of interpretation," "epistemic correlations," "coordinating definitions," "dictionaries," or "observational definitions," the correspondence rules had a threefold function: 1) They defined the theoretical terms, 2) they guaranteed the cognitive significance of these terms, and 3) they specified the experimental procedures by which the theory might apply to the phenomena.
Unfortunately, there are some manifest inadequacies of the correspondence rule approach. Take, for instance, a dispositional term like 'fragility'. How is this disposition definable in first order predicate logic? An object that is fragile and the one that is not fragile have no observational differences if neither one breaks. Fragility is a property about what would happen if the object in question were subjected to certain conditions that do not in fact occur. But talk of counterfactual or subjunctive conditionals takes us away from first order predicate logic into the land of intension -- non-extensional meaning -- something most philosophers of science wanted to avoid.
But there is a bigger issue. The correspondence rule approach presupposes that a theoretical term is identified with one experimental procedure. Unfortunately, this is generally not the case. There is no one-to-one coordinating definition for theoretical terms. An observational correlate to such terms is not found in one complete observation, but rather the theoretical term connects to many incomplete, partial observations. Thus, the effort began to give an alternative non-semantic account of how theoretical terms might have only a partial observational interpretation.
But now even more questions arise. When theoretical terms are provided only a partial observational interpretation, then what is their status? Since they no longer can the be linked by semantics to observational correlates, what is it to which they link?
Some espousing realism asserted that the terms of the theory actually refer to real entities that presumably exist apart from human awareness, perception, conception and language. Others counseling instrumentalism claimed that the terms are really short-hand ways of calculating and predicting observational results. While most adherents of the Received View were realists committed to Quine's notion that "to be is to be the value of a bound variable," the fact that a theoretical term is not exhausted by its observational interpretation neither entails realism nor anti-realism (instrumentalism).
A new modified Received View thus arose espousing indirect verification, a view summarized by A.J. Ayer this way:
A statement is indirectly verifiable if and only if in conjunction with certain other premises it entails one or more directly verifiable statements which are not deducible from the other premises alone.
Both the modified and original Received View were nonetheless committed to the legitimacy of the distinction between observational and theoretical terms. Examples of the former include 'black', 'cold', 'right of', 'shorter than', 'soft', 'volume', 'floats', 'weighs', 'wood', etc. Examples of the latter are 'mass', 'energy', 'electric charge', 'electron', 'hadron', 'temperature', 'virus', 'gene' or even 'ego'.
While this distinction might prima facie seem clear, it is not. It turns out that there is a theoretical component to any observational term. While 'ego' is a theoretical term in psychological theory, 'floats' has a theoretical component as well in the everyday "theory" of our involvement in the world. Moreover, we might speak about "observing" electrons, but what are the identity conditions of 'observe' when applied to electrons? Consider, "I see a leaf." Do all cultures have some non-theoretical identify conditions for 'leaf', or is that also a theoretical term. Simply put, it may be useful for us to talk about leaves as separate entities from the branches upon which they grow, but is there a fact of the matter here? Do putative observational terms come as self-identifying objects?
We will continue our discussion of the Received View in the next post which will contrast the syntactic view of scientific theory from the semantic view. Read on!
No comments:
Post a Comment