The sudden deaths of his two patrons in the same winter meant that Leibniz had to find a new basis for his career .
Leibniz promptly returned to Paris and not , as had been planned , to Mainz .
The sudden deaths of Leibniz 's two patrons in the same winter meant Leibniz Leibniz had to find a new basis for his career .
Leibniz promptly returned to Paris and not , as had been planned , to Mainz .