More than 250 years separate the publication of Baruch Spinoza's Ethics and Ludwig Wittgenstein's Tractatus Logico-Philosophicus. In Peeling Potatoes or Grinding Lenses, Aristides Baltas contends that these works bear a striking similarity based on the idea of "radical immanence." He analyzes the structure and content of each treatise, the authors' intentions, the limitations and possibilities afforded by scientific discovery in their respective eras, their radical opposition to prevailing philosophical views, and draws out the particulars, as well as the implications, of the arresting match between the two.