Quick quiz: What do Hinduism, transcendentalism, old-school conservatism, Traditionalism and Conservationism have in common?
They all view themselves as groundwork philosophies, or descriptions of how reality works, with advice on how to adapt to that. They are what can be called "Perennial Philosophies," in that they do not address moral ought, as a replacement for nature, as much as reverently describe nature and the time-proven, eternal ways of adapting to it. In these philosophies, each recommended action or value corresponds directly to a mathematical, informational tendency to both reality and the process of thought alike (a type of philosophy called idealism).
One good introduction to this is Aldous Huxley's cut-n-paste book, The Perennial Philosophy, in which he cites a wide variety of sources and explains their connection to this groundwork philosophy that manifests itself in every culture in some form -- and in rising cultures, becomes the dominant view.
Much as Hinduism considers all other religions to be a subset of Hinduism, Perennial Philosophies consider themselves inherent to reality, and so they view all other philosophies as means of studying reality -- a sleight-of-hand way of pointing out that reality itself, and even more importantly predicting how it responds to our actions, is indescribable, and we have many competing descriptions of it that must ultimately be put to the test of practice.
It's one of the more interesting books I have studied, because more than reading it, you go through each chapter and pick up its parable-like meanings and then review the citations offered, seeing how many connections from different ideas converge on each parable. For anyone who is frustrated with the modern division between liberalism and modern/liberalized conservatism, this is a breath of fresh air and a passage to hope for a realistic change.