In the summer of 5688 my father was in Marienbad. One of the elders of the "Enlightenment" was staying there s well and he came to visit my father. Hes asked my father about some profound subject and my father replied with an explanation according to chasidic doctrine.
The elder was pleased with answer and explanation and he said, "This is Chasidus?! It seems like a deep philosophical concept. What, then, is the difference between the logic of philosophy and that of Chasidus?"
My father replied: "My brother, Rabbis Zalman Aaron , once gave the following answer too that question. 'When a person studies philosophy, he ultimately sheds his tallis kattan and hat. And when a person studies Chasidus, he ultimately puts on a gartel and a yarmulke'.
"This is the truth.. Everything depends on the introduction and preparation for study. Philosophy is generally studied in a spirit of cynicism born of a desire to cast off the yoke of heaven. But Chasidus is studied in a spirit of warmth born of belief and acceptance of the yoke of Heaven and an awe of Heaven.
"This," my father concluded, "its the fruit of the devotion of the early chasidim to Chasidus. they bequeathed to their children and their children's children some spiritual lachuchis (moisture)(referring to an intuitive sense and warm regard for Chasidus.) so that a chasidic concept stick to them. A chasidic axiom is absorbed well by them and places them on the path of truth."
Taken from The Chasidic Heritage Series The four Wolds a letter by Rabbi Yosef Yitzhak Schneersohn of Lubavitch. Kehot Publication Society.