Theory of Science

Introduction

Bolzano’s main work appeared in 1837 in four volumes in Sulzbach in Bavaria, because after his dismissal he was barred from publishing in Austria. The subtitle calls it an attempt at a detailed and largely new presentation of logic. Its basic concepts are the “proposition in itself” (Satz an sich), the “idea in itself” and the “truth in itself”: contents that exist independently of anyone thinking them. Logical consequence is defined by systematically varying the ideas in a proposition and checking which truth values are preserved. Hardly read for decades, the book was brought back to attention by Husserl in his Logical Investigations; historians of logic see in it ideas later made precise by Tarski.

Connections

Criticizes

• Critique of Pure Reason1781 · Immanuel Kant