There is no general agreement of what space is, or time, or matter. In physics class we had to answer up quite quickly and brightly of course. They don't allow the philosphy dept in the same building as the physics and engineering dept for good reason.
Not sure if this is what you meant, but I'd hesitate to dismiss it as a purely philosophical question. For instance, the interaction between theorists and experimentalists has benefitted both many times over. Now, I don't know offhand if I'd want to spend $20 billion on a 100-km telescope... But I might be able to be convinced that it was desirable. :-)