I realized as Rabbi Hirshprung said on the Rebbe – Rabbi Hirshprung had a photographic memory and apart from the Rebbe, was by far the greatest scholar (at least in terms of knowledge) in the past generation

Even if a normal person would study 18 hours a day, whether Chassidus, Halacha, Gemarah etc. it would be impossible for them to be able to glean the insights the Rebbe saw – often for example being able to boil down literally hundreds of argument in Talmud to a single core disagreement resulting in the subsequent disagreements – in other words, he said, the Rebbe had a Divine intellect!