Hermann Grassmann’s contribution to Whitehead’s foundations of logic and mathematics

The title could sound presumptuous to a reader familiar with Gert Schubring’s volume [Schubring 1996a] devoted to Hermann Grassmann. There, we learn from Ivor Grattan–Guinness and Volker Peckhaus that, if Herman Grassmann contributed to logic at all, his contribution was not as substantial as that of his brother, Robert.