Permit me to answer the question perhaps indirectly but with some relevance, and without providing a reading recommendation. If there be a single influence in my understanding of what philosophizing is, and my continued choices to undertake doing it, I would have to point to the works and life of Nietzsche as this source of "inspiration."
I use the word "works" because his was not a thinking that distilled itself in one particular work; in fact, one can see the growth and transformation of many of his fundamental viewpoints and positions if one reads his works sequentially and with sympathy.
I use the word "works" also because it was not the particular answers he sometimes proposed that influenced me, but that he risked so much in the questions he asked---and, when I first read him, that such questions could be asked at all.
From reading him, I was lead to something like a "perspectivalist" position, certainly towards my grounding my own philosophy in what would commonly be called "existentialism," where Nietzsche's thought has been so fundamental.