Who could draw the conclusions from Aristotle's four propositions? 
Aristotle's four propositions is as follows: 
(1) A belongs to all B; 
(2) A belongs to no B; 
(3) A belongs to some B and 
(4) A does not belong to some B 

Let R be a binary relation R (belongs to). Then we have...

1	ALL(b):R(a,b)
	Premise

2	~EXIST(b):R(a,b)
	Premise

3	EXIST(b):R(a,b)
	Premise

4	EXIST(b):~R(a,b)
	Premise