Pascal-Emmanuel Gobry reminds us that Descartes, when formulating his ontological argument for the existence of God, approached the matter as a mathematician and as a theist trained in the classical philosophical tradition. As a student of mathematics, “he understood that what is even conceivable in any given geometric universe is determined by the axioms that rule that universe.” As part of the classical philosophical tradition, he approached philosophy more as a process and a way of life than as a doctrine.
The underlying lesson here is an important one for students of philosophy (and any other intellectual discipline): all philosophy is contextual, so every philosopher must be read in context. To understand a philosopher, you can’t just look at what was said. Philosophers have specific agendas, tasks, desires, and motivations. They’re asking specific questions–and not others. Their courses of thought are established and limited by particular presuppositions and guided by particular methodologies.
However immaculate their logic, however focused they are on the pursuit of truth–philosophers reason in terms of the worlds in which they live. In philosophy, there is no truth apart from history. Descartes’ ontological argument is not Anselm’s, not only because the formulations were different, but was because each thinker was doing something different, with different reasons, and within different circumstances.
Your own interpretation of a philosopher will be contextual as well. Even if you reside more or less in the same time and place as the thinker you’re reading, you have your own agenda, your own presuppositions, and your own set of circumstances. You might succeed in putting on your Descartes hat or Nietzsche hat or Simone de Beauvoir hat, but it will always be you wearing it. This limits you, but on the plus side, it also means that you’re in a place to say something new. Not only can their worlds expand your own, you can bring your own world into theirs!