12 INTRODUCTION TO PHILOSOPHY OF SCIENCE 



in so far as they have content, to propositions of psychology 

 and of sociology, and, in so far as they have no content, to 

 pseudo-propositions. The total range of sensible proposi- 

 tions, then, reduces to two classes: material propositions, 

 which assert about facts and therefore have empirical 

 sense; and formal propositions, which assert about symbols 

 and therefore have sense only in so far as symbols are them- 

 selves facts of a certain kind. For Wittgenstein even the 

 propositions of logic are without sense; for Carnap they 

 possess sense of their own peculiar kind. 



What may be said in estimation of this important theory 

 of the interrelation of science and philosophy? Its neatness 

 gives it a strong appeal. Furthermore, any technique which 

 offers a method for simplifying the philosophical task by 

 eliminating a large number of pseudo-problems is certain 

 to be looked upon with favor. Again, even apart from the 

 general presuppositions of the position, the analysis of 

 logical techniques and the general contributions to logical 

 theory which have been made by this group have given it a 

 place of importance in the contemporary scene. But that 

 philosophy is adequately defined merely as the logical 

 analysis of symbols is, perhaps, questionable. Certainly 

 there are many highly general propositions about the world 

 which are not strictly a part of science and yet which are 

 not merely about symbols. Such propositions tend to be 

 considered as symbolic since their high generality suggests 

 the impossibility that they should be false, and they are 

 consequently taken to be legislative over the world merely 

 by virtue of an arbitrary use of symbols. In spite of the fact 

 that a proposition such as " an event is not both p and not-p ,! 

 obviously asserts something about events, it is presumed 

 by this group to be merely an assertion about symbols, i.e., 

 "the symbols 'p' and 'not-p' are so defined as to make false 

 any proposition in which they are jointly predicated of an 

 event." A definition of philosophy which would retain its 

 obvious empirical reference seems to be preferable to one 

 which reduces it to symbolic analysis. Yet, in spite of this 



