It was during his stay in Milan when he was in his thirties and forties that he would begin his notebooks in earnest and mature and develop into a powerful thinker, bringing together Florence’s more Neoplatonic philosophy with a Milanese Aristotelian approach and adding his own belief systems surrounding his approach to man and nature. His intellectual development during this time was prodigious and seems to have exploded into an understanding of the underlying unity of nature through his development as a natural philosopher.
