This question is one that I have wrestled with a lot, in part because it’s fairly unconventional for academic philosophers to write biographies. There are some notable exceptions, but it’s often not considered a philosophical enterprise to write the history of a person’s life. In the philosophy of biography, there are two opposing camps: on the one hand, you get compartmentalists, who say that a life is irrelevant to the interpretation of the work and vice versa. On the other hand, at the other end of the spectrum, you get the idea that the person’s life is going to be a key that unlocks the understanding of their work. They might even go so far as to say that you will not understand the work of that philosopher unless you know about the context in which they lived, and so forth.