The Rebbe thanks Dr. Shashkes for his books and their meeting, emphasizing that a Jew must bring light wherever they go. He highlights the divine purpose of Jewish dispersion—to elevate their surroundings spiritually—and encourages utilizing every opportunity to spread warmth and holiness, trusting that Hashgacha Pratis provides the means to do so.
https://www.torahrecordings.com/rebbe/igroskodesh/014/005/5093