My professors did not agree with me. As the geologists used to kid us, "Geologists study the earth's surface, Geographers study the earth superficially". There was a great effort made when I was a geography grad student to develop formal theoretical concepts with mathematical formulations for things like Central Place Theory or Regional Geography, but although these were useful concepts, they certainly didn't demand or require the formalism and those efforts were not too convincing.

Again, today there is a different rigor to the field, Geographers now tend to study the technologies used to study the earth (remote sensing, geodesy, aerial stereo photography, computer mapping, interactive cartography, navigation)---what is generally lumped together under the catch-all "Geomatics". But I still have to remind most folks that although I am indeed a geographer, I am not an expert on state capitals, the names of rivers, or county boundaries.