Yes propositins.
Science bases propositions on a set of unambiguous units of measure based on the kilogram, second, and meter. Systems International.
Today it is evolution and still cosmology.
Evolution proposes more from the point of life ALREADY existing oddly enough. With that line of thought, rather than Creation V Evolution ... I wondering how interesting Abiogenesis V Creation would be? Both concepts are in the context of coming into existence.
Evolution is a process that acts on populations of living things. It does not address the origin of life. Abiogenesis is a process that generates self-replicating molecules using existing matter and energy gradients. Both evolution and abiogenesis are fields of scientific study. Creationism, on the other hand, is NOT a field of scientific study, in that it has no empirical basis. It is merely an unsupported claim based on religious beliefs.
While evolution/abiogenesis and creationism both make claims about the nature of reality, they are not equally credible. You appear to be confused about this distinction, so I am pointing it out.
You'd think that the two would be combined - stating strongly under one proposition, presenting the FULL picture of the existence of life. (if not for being over cautious perhaps)
Do we need to know where matter came from in order to describe how matter behaves in spacetime? Is Newton's or Einstein's theory of gravity any less true or any less meaningful because they don't describe where matter comes from?
We often hear atheists always keeping seperate the two with phrases like " You don't know anything about evolution because abiogenesis has nothing to do with evolution" blah blah blah. Ah ...so NO starting-point then, one must be asking? A little like magic or faith?
Ultimately, everything in the observable universe is the way it is because of the conditions/state of the universe at the Big Bang. To someone who is deeply ignorant of how the universe works, it may seem like magic or faith. But ignorance can be cured; you just have to be willing to learn.