After graduating he remained at the University of Lvov and he was awarded his doctorate in June 1937. Kac had decided, before his doctorate was awarded, to try to leave Poland (,):
Pagkatapos graduating siya ay nanatili sa University of Lvov at siya ay iginawad sa kanyang titulo ng doktor sa Hunyo 1937. Kac had nagpasya, bago ang kanyang titulo ng doktor ay iginawad, para mag-iwan Poland (,):