28 JOHN A. OESTERLE 



induction: no one reporting about swans had ever seen a black 

 one. 



We come therefore at once to the following question. Since 

 " white," as a common property, was not certain, why is it 

 that we could use the universally distributive ' all ' and say 

 that all swans are white? Why not use a roundabout expression 

 and state: " It appears that some, if not all, swans are white." 

 Or why not say, even more simply, " swan is white," as we say 

 " man is white." In this more simple way of putting the matter 

 we would be plainly predicating something of a universal 

 (" swan ") by reason of something found in one or some 

 individuals. The point then is whether this would be regarded 

 as a universal ut nunc, a universal " for the time being." Pre- 

 sumably not, for what we are aiming at is an enunciation like 

 " man is an animal," an essential predication. But why use 

 this mode of enunciation before it is warranted? 



What we are in fact faced with is two distinct modes of 

 essential predication: a true one and a hypothetical one. What 

 is the foundation for this distinction? Why are hypothetically 

 essential predications required? Why not use unambiguous 

 circumlocutions that show the essential predication to be only 

 hypothetical? After all, many essential predications are in fact 

 no more than hypothetical. 



To answer such questions — which in effect are one question — 

 about the distinction between true and hypothetical essential 

 predications, it will be opportune, first of all, to make a further 

 distinction by comparing the notion of " triangle " with what 

 we intend by " swan." We can define the first as to what it is, 

 namely a three straight-sided figure whose exterior angle is 

 equal to the two opposite interior angles. But what about 

 " swan "? We define, not the swan, but the name by pointing 

 to individual instances, or by describing the figure and habits 

 that set swans apart from chickens, turkeys, geese, and so on. 

 Now surely there must be in nature something that accounts 



