Jon Barwise
Kenneth Jon Barwise ( ; June 29 , 1942 – March 5 , 2000 ) was an American mathematician , philosopher and logician who proposed some fundamental revisions to the way that logic is understood and used . 
<triplet> Jon Barwise <subj> June 29, 1942 <obj> date of birth <subj> March 5, 2000 <obj> date of death