He embraced a position on the left wing of the party endorsing an open rebellion in March 1921 in central Germany and placed himself hereby in opposition to the leader of the party, Paul Levi.
Ia menganut posisi sayap kiri di partai tersebut, mendukung pemberontakan terbuka pada Maret 1921 di Jerman tengah dan menentang pemimpin partai Paul Levi.