Torah im Derech Eretz
Among the Rav's philosophical views was the concept of Torah im Derech Eretz, which was first introduced in Germany by his grandfather, Rav Shamshon Raphael Hirsch. The Rav built the Frankfurt community and its schools in Washington Heights on this approach.
Source: Philosophy of Rav Yosef Breuer, following Rav Shamshon Raphael Hirsch