[photochemsyn]

There are a great many questions of interest to humans that science cannot provide any truth value for. Science cannot answer metaphysical questions like "are we all living in a perfect simulation" (in this case, no experiment or observation could reveal the simulation, barring something like simulation glitches) or "why does the universe even exist - why is there something when there could be nothing?". Hence science is quite limited in scope.

One might argue that mathematics gives us an unambiguous definition of truth, but that's only in the context of a given set of axiomatic basis, and if you introduce you other favorite choice of axioms, well, where's the truth of which are the 'right' axioms?

More fantastically, one could argue that supernatural beings are constantly intervening in the physical universe, but only when they're sure nobody is watching them. This all leads to a notion that science will always leave room in the world for mysticism of various kinds, which is fine.