In 1678, while studying at the University of Frankfurt an der Oder, Tobias Cohen — better known as Tuvia ha-Rofeh, or “Tuvia the Doctor” — collaborated with fellow Polish Jew Felix Gabriel ben Moses of Brody to produce this striking ilan. Though not a kabbalistic ilan, this arboreal visualization of Hebrew grammar is distinguished for its rigorous scholarship and striking aesthetic clarity. It testifies to the versatility of the tree schema, which had been used for centuries to show genetic lineage as well as the “great chain of being” before being widely adopted by kabbalists to visualize the sefirotic array. 
 
Cohen and Gabriel had earned their place at the university through a rare act of tolerance by Frederick William, the Great Elector of Brandenburg, who not only granted them admission but also awarded them stipends. In return, the students agreed to learn German and serve as Hebrew instructors — perhaps even to the elector himself.
 
The Tree of Grammar they created during this time reflects that scholarly exchange. It is precise, colorful, and symmetrical, visually expressing the linguistic architecture of the Hebrew language. Unlike ilanot designed for mystical contemplation, this work belongs to a lesser-known but no less fascinating lineage of ilanot devoted to grammar and logic.
 
Cohen would later become a prominent physician and the author of Ma‘aseh Tuvia, a foundational work of early modern Jewish science and medicine that has remained in print since its publication in 1707. This artifact offers a rare glimpse into his early intellectual world and the vibrant confluence of Jewish learning and European humanism.