Arntz was a German modernist artist and was known for his black and white woodcuts. Starting 1926, Otto Neurath contacted Arntz to collaborate in designing pictograms for Isotype. Since the beginning of 1929, Arntz worked at the same museum directed by Neurath. Throughout his career, Arntz designed around 4000 pictograms. Arntz and Neurath created a large collection of visual statistics and their system is now called infographics.