Moving on from Implicit Definitions 51

In chapter 1 we examined Schlick's use of implicit definitions and saw that they would require some modification along the lines that Carnap was to suggest in the Aufbau. As we noted, Schlick abruptly stopped talking about them in 1927, despite having until then considered them "absolutely fundamental and of immeasurable import for the whole of philosophy," (1926, [1979b, p.102]). In this section we will examine how Wittgenstein's account of the internal properties of terms allowed Schlick to reintroduce to science ostensive definitions which he had previously rejected.

Both Schlick and Wittgenstein agree that the meaning of most of our everyday words is settled by explicit definition in terms of other words. The question is: what happens when we run out of other words? How do we define the most simple words for the most simple objects? For the sake of example, I'm going to pretend that colours like red are objects.

Wittgenstein's view in the TLP, which we examined above on pages 34-35, was that the proposition "this is A" would serve to explain the meaning of "A" to someone. Aside from the imprecision, this introduced a problem which Wittgenstein was aware of by the time of his Philosophical Remarks (1930, [1975]), and which Schlick had written of in 1925 (AE: pp.75-76). The problem is that the same utterance cannot be a proposition and a definition at the same time. A definition is a rule. It is not true or false, it merely sets up an arbitrary relation between symbols (or between concepts for early Schlick). On the other hand, it is an essential feature of propositions that they can be either true or false. The difference becomes clear when we analyse the sentences in question, as we did in chapter 1, pages 17-18. "All

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bodies are heavy" will be equivalent to "all extended heavy things are heavy" in the case of a definition, or "all extended things are heavy" if it's a proposition. If "A" gets its meaning from the sentence "this is A" then that sentence could be analysed as "this is this". On the other hand, if "this is A" is a proposition then we must take "A" to mean something in particular, which this may or may not be.

Wittgenstein's view in the Philosophical Remarks is that "in a certain sense, the use of language is something that cannot be taught, i.e. I cannot use language to

teach it … And that of course is just another way of saying: I cannot use language to

get outside language," (1930, [1975, §6]). The idea here is that the attempt to explain how we learn language by reference to propositions that would teach us was misguided from the beginning. The manner in which we learn the names of objects cannot be through grasping a proposition. It must be outside of language, and that puts it beyond the scope of a linguistic inquiry. Within the language, words for complexes are defined in terms of names for the objects which make up said complex, and that is all that we need to say about that.

Meanwhile, Schlick is moving from a position on which some terms are defined by their intuitive content and some by their position in the axioms of science, to a position on which all terms are defined by their relations to other terms in an interconnected network. The big difference between Schlick’s earlier and later

positions, as far as definitions go, is that in AE he still accepts that some concepts will be defined concretely. For early Schlick, there is an everyday language of experience which we must coordinate with the precise scientific concepts but which itself is imprecise and insufficient for scientific purposes. By F&C, however, formal relations form the basis of definition for not only the abstract concepts of science, but also those terms that appear to be defined by the intuitive experience with which they are associated. We will be looking at structural definitions for terms like

“green” and “warm” alongside less controversial theoretical terms such as “photon” and “energy”.

For Wittgenstein, names denote objects and resist definition of any sort. The first point to note is that there is nothing imprecise about the denotation of a name

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being an object. Schlick’s objection to concrete definitions in science was aimed at the fixing of the reference of a name by a recollected sense image, which is not precise, but vagueness is not a feature of reality. The question is how we come to set up the relation between the name and the object, and in F&C Schlick makes it clear that he thinks we learn language by having the situations in which propositions are verified indicated to us. That means presenting us with the objects named in the relevant proposition.

The important idea introduced by Wittgenstein is that of an object’s internal properties. Objects, by their very nature, show something about the possibilities of their combination with other objects – this is what is reflected in the grammar of a word, which tells us the possibilities for combining the word with other words to form a meaningful sentence. What this means is that it is possible to learn something meaningful about objects by being presented with them, without claiming that the intuitive content of the experience of the object is part of the meaning of the word thereby learned. Being presented with a green leaf and being told “this is green”

allows us, after a few more ostensive acts clarify that it is the colour and not the

shape that we’re interested in, to attach a meaning to the word “green” based on the

internal properties of green, not merely on the phenomenal content of greenness. The difference between this procedure and the procedure of AE (and the procedure of structure descriptions suggested by Carnap) is that we can understand

“green” as referring specifically to an object with such-and-such internal formal properties, and not merely as whatever in fact fits into a certain place in the system. The system is important for knowledge, but the meaning of a word is determined by the internal properties of the object which that word names, and these properties can be learned in the process of ostensive definition.

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