Suppose that his impression--the elderly Jew at Frankfort seemed to have something like it--suppose in spite of all presumptions to the contrary, that his impression should somehow be proved true, and that I should come actually to share any of the ideas he is devoted to? 
The elderly Jew at Frankfort seemed to have the same impression. Suppose that this should somehow be proved true, and that I should come to share the ideas he is devoted to? 