The sources of Kolmogorov's Grundbegriffe

Andrei Kolmogorov's Grundbegriffe der Wahrscheinlichkeitsrechnung put probability's modem mathematical formalism in place. It also provided a philosophy of probability-an explanation of how the formalism can be connected to the world of experience. In this article, we examine the sources of these two aspects of the Grundbegriffe - the work of the earlier scholars whose ideas Kolmogorov synthesized