Last week I took an intellectual road trip back nearly a century and explored the historical context and scientific logic by which R. A. Fisher definitively fused Mendelian genetics with quantitative evolutionary biology. In the process he helped birth the field of population genetics. While the genetics which we today are more familiar with begins at the biophysical substrate, the DNA molecule, and the phenomena which emerge from its concrete structure, population genetics starts with the abstract concept of the gene. This abstraction and its variants are construed as algebraic quantities from which one can infer a host of dynamics. These are the processes which are the foundations of evolutionary change, as population genetics flows into evolutionary genetics, and ultimately the raw material of natural history.