After that, he began studying mathematics at the University of Berlin under Leopold Kronecker, Lazarus Fuchs, and Wilhelm Dilthey.

Since this area was poorly represented at Berlin, he moved to the University of Halle, where he obtained his doctorate in 1892 under Albert Wangerin with a dissertation on the topic Ueber eine gewisse Klasse continuierlicher Gruppen und ihren Zusammenhang mit den Additionstheoremen ("On a certain class of continuous groups and their relation to addition theorems").

However, since he held no permanent position there, he went to Berlin in 1903 to work as the Chief Actuary for the German subsidiary of the New York Mutual Life Insurance Company.

Compared to the current structure of probability theory, his work only lacked the technical condition of sigma additivity.

However, in contrast to Kolmogorov, Bohlmann failed to prove significant theorems within his axiomatic framework.