I am not by any means a philosopher, although I have worked with some talented people in the discipline. But certain philosophical concepts deeply inform the way I think about the world. The idea of 'opposing truths at extremes' is a powerful concept that I came to appreciate in my twenties.
A recipe I've seen work in early-stage startups is a small tight-knit group of passionate people who are obsessed with their vision of how to fix a particular industry. Conversely, teams composed of people with a lot of specialized experience at running a large business are not as likely to do very well in the first year or two of a startup.
Inasmuch as there is a useful purpose to what we do as VCs, I tend to think it's our duty not only to mentor entrepreneurs and executive teams, but also to learn from them and the others involved. We can then pass on lessons to aid the startup ecosystem and help businesses succeed and grow their impact.
Marketing is your battle plan for the sales team - it's about defining the landscape. Marketing is doing cohort analysis and understanding exactly what possible customers are out there. It's understanding not only which customers will respond to what messages, but also how customers will become clients if you include certain product features.