In the course of historical development a word frequently changes its meaning. And it also happens at times that a word loses its old sense without acquiring a new one. It is thus that a pseudo-concept arises.
What, now, is the meaning of a word? What stipulations concerning a word must be made in order for it to be significant? (It does not matter for our investigation whether these stipulations are explicitly laid down, as in the case of some words and symbols of modern science, or whether they have been tacitly agreed upon, as is the case for most words of traditional language.) First, the syntax of the word must be fixed, i.e. the mode of its occurrence in the simplest sentence form in which it is capable of occurring; we call this sentence form its elementary sentence. The elementary sentence form for the word ‘stone’ e.g. is ‘x is a stone’; in sentences of this form some designation from the category of things occupies the place of ‘x’, e.g. ‘this diamond’, ‘this apple’. Secondly, for an elementary sentence S containing the word, an answer must be given to the following question, which can be formulated in various ways:
(1) What sentences is S deducible from, and what sentences are deducible from S?
(2) Under what conditions is S supposed to be true, and under what conditions false?
(3) How is S to be verified?
(4) What is the meaning of S?
… In the case of many words, specifically in the case of the overwhelming majority of scientific words, it is possible to specify their meaning by reduction to other words … e.g. “‘arthropods” are animals with segmented bodies and jointed legs’. Thereby the above-mentioned question for the elementary sentence form of the word “arthropod”, that is for the sentence form “the thing x is an arthropod”, is answered: it has been stipulated that a sentence of this form is deducible from premises of the form “x is an animal”, “x has a segmented body”, “x has jointed legs”, and that conversely each of these sentences is deducible from the former sentence. By means of these stipulations about deducibility (in other words: about the truth-condition, about the method of verification, about the meaning) of the elementary sentence about “arthropod”, the meaning of the word “arthropod” is fixed. In this way every word of the language is reduced to other words and finally to the words which occur in the so-called “observation sentences” or “protocol sentences”. It is through this reduction that the word acquires its meaning.
For our purposes we may ignore entirely the question concerning the content and form of the primary sentences (protocol sentences) which has not yet been definitely settled. In the theory of knowledge it is customary to say that the primary sentences refer to ‘the given’; but there is no unanimity on the question what it is that is given. At times the position is taken that sentences about the given speak of the simplest qualities of sense and feeling (e.g. ‘warm’, ‘blue’, ‘joy’ and so forth); others incline to the view that basic sentences refer to total experiences and similarities between them; a still different view has it that even the basic sentences speak of things. Regardless of this diversity of opinion it is certain that a sequence of words has a meaning only if its relations of deducibility to the protocol sentences are fixed, whatever the characteristics of the protocol sentences may be; and similarly, that a word is significant only if the sentences in which it may occur are reducible to protocol sentences.
Since the meaning of a word is determined by its criterion of application (in other words by the relations of deducibility entered into by its elementary sentence-form, by its truth-conditions, by the method of its verification), the stipulation of the criterion takes away one’s freedom to decide what one wishes to ‘mean’ by the word. If the word is to receive an exact meaning, nothing less than the criterion of application must be given; but one cannot, on the other hand, give more than the criterion of application, for the latter is a sufficient determination of meaning. The meaning is implicitly contained in the criterion; all that remains to be done is to make the meaning explicit.
Let us suppose, by way of illustration, that someone invented the new word ‘teavy’ and maintained that there are things which are teavy and things which are not teavy. In order to learn the meaning of this word, we ask him about its criterion of application: how is one to ascertain in a concrete case whether a given thing is teavy or not? Let us suppose to begin with that we get no answer from him: there are no empirical signs of teavyness, he says. In that case we would deny the legitimacy of using this word. If the person who uses the word says that all the same there are things which are teavy and there are things which are not teavy, only it remains for the weak, finite intellect of man an eternal secret which things are teavy and which are not, we shall regard this as empty verbiage. But perhaps he will assure us that he means, after all, something by the word ‘teavy’. But from this we only learn the psychological fact that he associates some kind of images and feelings with the word. The word does not acquire a meaning through such associations. If no criterion of application for the word is stipulated, then nothing is asserted by the sentences in which it occurs; they are but pseudo-statements.
Secondly, take the case when we are given a criterion of application for a new word, say ‘toovy’; in particular, let the sentence ‘this thing is toovy’ be true if and only if the thing is quadrangular. (It is irrelevant in this context whether the criterion is explicitly stated or whether we derive it by observing the affirmative and the negative uses of the word.) Then we will say: the word ‘toovy’ is synonymous with the word ‘quadrangular’. And we will not allow its users to tell us that nevertheless they ‘intended’ something else by it than ‘quadrangular’; that though every quadrangular thing is also toovy and conversely, this is only because quadrangularity is the visible manifestation of toovyness, but that the latter itself is a hidden, not itself observable property. We would reply that after the criterion of application has been fixed, the synonymy of ‘toovy’ and ‘quadrangular’ is likewise fixed, and that we are no further at liberty to ‘intend’ this or that by the word.
Let us briefly summarize the result of our analysis. Let ‘a’ be any word and ‘S(a)’ the elementary sentence in which it occurs. Then the sufficient and necessary condition for ‘a’ being meaningful may be given by each of the following formulations, which ultimately say the same thing:
1 The empirical criteria for ‘a’ are known.
2 It has been stipulated from what protocol sentences ‘S(a)’ is deducible.
3 The truth-conditions for ‘S(a)’ are fixed.
4 The method of verification of ‘S(a)’ is known.
Many words of metaphysics, now, can be shown not to fulfil the above requirement, and therefore to be devoid of meaning … [An] example is the word ‘God’. Here we must, apart from the variations of its usage within each domain, distinguish the linguistic usage in three different contexts or historical epochs, which, however, overlap temporally. In its mythological use the word has a clear meaning. It, or parallel words in other languages, is sometimes used to denote physical beings which are enthroned on Mount Olympus, in Heaven or in Hades, and which are endowed with power, wisdom, goodness and happiness to a greater or lesser extent. Sometimes the word also refers to spiritual beings which, indeed, do not have manlike bodies, yet manifest themselves nevertheless somehow in the things or processes of the visible world and are therefore empirically verifiable. In its metaphysical use on the other hand, the word ‘God’ refers to something beyond experience. The word is deliberately divested of its reference to a physical being or to a spiritual being that is immanent in the physical. And as it is not given a new meaning, it becomes meaningless. To be sure, it often looks as though the word ‘God’ had a meaning even in metaphysics. But the definitions which are set up prove on closer inspection to be pseudo-definitions. They lead either to logically illegitimate combinations of words, or to other metaphysical words (e.g. ‘primordial basis’, ‘the absolute’,
