The first part deals with the problem of the external form of ostensive definition. It is concluded that the definition statement is not complete. The proper form of this statement is not a sentence, but a sentential function, namely a sentential function of the type: “IIx [N(x) = x is in the respect R and in the degree D such as A, B ... and not such as K, L ...]” where “N” stands for the term being defined.

Thus the ostensive definition informs about the criteria of applicability of the defined term in a partial way only, and the rest must be supplied by the addressee for whom the given definition was destined.

In the second part the conditions are analysed on which depends the possibility of solving that problem, and consequently the conditions on which depend the informational value and the efficacy of ostensive definition. The concluding remarks deal with the properties of the terms introduced by the ostensive method.

In following paper an attempt will be made to analyse the statistical relationships between variables as the functions of causal relations existing between them. Our basic assumption here is that statistical relationships between traits, events, or characteristics of objects, may be logically derived from the pattern of their mutual causal connections, if this pattern is described by appropriate concepts and with sufficient precision.

The first part of the paper presents basic concepts, which according to author's view may serve for the description of different patterns of causal relations in such a way, that statistical relationships corresponding to each pattern may be derived. It gives also examples of such a derivation for some less complicated cases. The second part of the paper is an attempt of application of proposed method to the understanding and critical consideration of some standard techniques of statistical analysis, especially those mostly used in social sciences.

The problem I shall discuss is specific, even minute. Yet, being philosophical, it arises and can be profitably discussed only in a context anything but minute, namely, that of a conception of philosophy and its proper method. I could not possibly unfold my conception once more for the sake of a minute problem. Nor do I believe that as things now stand this is necessary. I shall merely recall two propositions which are crucial in the context, and, in stating them, shall freely use its vocabulary. The undefined descriptive terms of the ideal language all refer to phenomenal things wholly presented. These things all are either individuals or characters, and, if characters, either relational or nonrelational. These are the two propositions. It may throw light on another crucial point not always well understood if I imagine someone to ask: Wholly presented to whom ? The answer is: To the person to whose world the philosopher, who, himself always speaks commonsensically, fits the ideal language.

C. S. Peirce argued that inductive reasoning and probability judgments are adequately secure only in the indefinitely long run, and that therefore it is illogical to employ these modes of inference unless one's chief devotion is to the interests of an ideal community of all rational beings, past, present, and future. He thought of this devotion as a “social sentiment”, involving self-sacrifice. An examination of his argument shows that the attitude presupposed by his conceptions of induction and probability is in fact not self-sacrificial and is social only in a very special sense. Furthermore, it seems doubtful that this attitude is characteristic of practicing scientists; and this is a reason for questioning Peirce's analysis of induction and probability.

Many pragmatic philosophers insist that causality in human behavior is to be explained by psychological field theorism rather than by modern behaviorism. This paper attempts to demonstrate (1) that pragmatists often support one aspect of an untenable disjunction in psychological theory, (2) that the asserted disjunction is but a methodological distinction, and (3) that the causal order in human behavior is most likely to be profitably described, predicted, or explained by the methods of modern behaviorism.

This paper offers a refutation of P. Duhem's thesis that the falsifiability of an isolated empirical hypothesis H as an explanans is unavoidably inconclusive. Its central contentions are the following:

1. 1. No general features of the logic of falsifiability can assure, for every isolated empirical hypothesis H and independently of the domain to which it pertains, that H can always be preserved as an explanans of any empirical findings O whatever by some modification of the auxiliary assumptions A in conjunction with which H functions as an explanans. For Duhem cannot guarantee on any general logical grounds the deducibility of O from an explanans constituted by the conjunction of H and some revised non-trivial version R of A: the existence of the required set R of collateral assumptions must be demonstrated for each particular case.

2. 2. The categorical form of the Duhemian thesis is not only a non-sequitur but actually false. This is shown by adducing the testing of physical geometry as a counterexample to Duhem in the form of a rebuttal to A. Einstein's geometrical articulation of Duhem's thesis.

3. 3. The possibility of a quasi a priori choice of a physical geometry in the sense of Duhem must be clearly distinguished from the feasibility of a conventional adoption of such a geometry in the sense of H. Poincaré. And the legitimacy of the latter cannot be invoked to save the Duhemian thesis from refutation by the foregoing considerations.

It is shown that the logical theory of belief statements must be prepared to take into account relationships among statements which are subtler and more delicate than is requisite in other contexts. It is necessary here to draw distinctions (of a modal and semantical character) which the standard assertory logic can ignore with impunity. This is due to the fact that it is entirely possible to be in ignorance of various logical relationships (eg., entailment, equivalence, etc.) that in fact obtain among believed statements, and so, for example to believe the premisses of a valid deductive argument, and yet disbelieve the conclusion which follows from them. The implications of such difficulties for the logic of belief statements are examined.