Michael Josef Fesl

The most important and extensive of Bernard Bolzano’s (1781–1848) correspondences is the one with his student and friend Michael Josef Fesl (1788–1864) In total, the two exchanged around 730 letters. Due to the large number of letters in the Bernard-Bolzano-Gesamtausgabe, only the letters from the teacher to his student are published from 1831 onwards, so Fesl's letters to Bolzano appear in the Beiträge zur Bolzano-Forschung. The present volume contains 59 letters that Fesl wrote to his “most beloved teacher and friend” in the years 1842 to 1845. The smaller number of letters compared to other years is due to a period of crisis that the two experienced due to the death of key figures and which also put their relationship to the test. A number of letters address the deterioration in Bolzano's health that occurred during this time (and Fesl's worries about this). Even more important, of course, are Bolzano's publication projects and his preoccupation with new projects, particularly concerning the foundations of mathematics as well as aesthetics.