Depends on how you're looking at things. If you want just one key that unlocks all the doors to provide you with what the true nature of things is, no matter the form, then that key is Higher Consciousness. HC is not a religion or methodology or doctrine. It just means to see things as they are. Once you understand the underlying nature of things, (including yourself), then that understanding extrapolates to everything. If you want to know more about the appearances and behavior of phenomena, then science is the tool you need. However, as both ben and I implicate, the understanding puts the science into context. You don't get real understanding with science; you get factual knowledge.