One of these is easy. The raw material of science is observations, and observations have a location in spacetime. Without spacetime, there can't be observations, so science can't tell us anything about how spacetime itself came to be. Science cannot begin with truly nothing (no energy, no physical laws) as a starting point. The conservation of energy (including mass-energy á lá E=mc²) says that the amount of energy in (our?) universe is constant—but can say nothing about where that non-zero amount of energy came from. It cannot possibly hope to observe the beginning moment itself, and our ability to reason back in time towards that moment from things we can observe is dependent on invoking physical laws, the origin of which themselves require an explanation. So ultimately, we need to make some assumptions about why things exist, or science can't even get started. This is why I say that philosophy is the sole authority for origins.

Arguing that theology has no authority about natural history is more difficult. Here I am going to first use a theological argument and then an argument from history. (For those of you who don't care about theology, this whole paragraph is moot anyway.) 2 Timothy 3:16-17 says, “All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness, so that the man of God may be thoroughly equipped for every good work.” This, to me, is the Bible's own testimony about its authority and purpose: spiritual instruction for moral living. Therefore I do not believe that the Bible claims to be an authority on natural history. This is fortunate, because attempts to use Biblical narratives and statements to illuminate natural history have all disappointed, and efforts to shoehorn physical evidence into conformity with the Bible are embarrassing. Two examples suffice: the persecution of Bruno and Galileo based on 1 Chr 16:30, Ps 93:1 and 96:10 (“The earth is firmly established and cannot be moved”) and Eccl 1:5 (“The sun rises and the sun sets, and hurries back to where it rises.”), and the efforts of the Institute for Creation Research and others to argue that the Grand Canyon and seashell fossils on mountaintops are all caused by Noah's Flood. The Bible is a lousy science text, and those who try to use it as such set it and themselves up for ridicule IMO.

The one area of natural history (using the definition above) where I might be tempted to invoke Complementary Perspectives is when it comes to matters of why humans behave the way they do. Only if I were convinced that my personhood is a purely material artifact of the neurons in my brain could I get away with relying only on science for explaining how people's personalities get to be the way they are and why people do the things they do.

As for cosmology (how did the structure of the universe get to be the way it is today) and biological evolution (how did the diversity and adaptation of living things on Earth come about), these both have starting points: Big Bang theory starts with a singularity, the compression of the universe into an infinitely dense, infinitesimal volume; biological evolution starts with abiogenesis, the first thing that can be labeled, “alive.” The singularity is on the frontier of origins and where the singularity came from (or if you prefer where the multiverse from which many singularities arises came from) cannot be answered by science—but what happened after the singularity began to exist can be answered by science. Abiogenesis on the other hand is a prime candidate for a purely natural explanation because there were raw materials for it, the unliving things that comprised the first living thing, already in the universe. Where these came from can be answered wholly by natural history, because there is room earlier than the abiogenesis event before you get to the dawn of time. So one starting point is definitely in the realm of philosophy, and the other is arguably in the realm of science, but in both cases once the processes get started they are purely natural history. I therefore give science all authority in cosmology and biological evolution and do not look to Scripture for any insights into their past history, current operation, or future effects.

Next up: my thoughts on the question, “Does the cause of the existence of the universe have any effects on its natural history?” In other words, what I think of Intelligent Design.