But until someone tells us the objective test to distinguish the immaterial from the imaginary and the non-existent, we have no concept of what 'immaterial' might mean.
Which is really nobody's problem but yours. Most of us have a mind that is comfortable with unmeasurable concepts, and things we may not be able to demonstrate with objective tests. There is no objective test for emotional states, as an example, but the ability to recognize and deal with subtle differences in emotional states is critical to our survival as humans. Indeed critical to the survival of most higher animals.
Shall we not consider the emotional state of our neighbors just because BlĂĽ can't measure them? I don't know about you Kemo sabe but Palin appears to me to hate atheists. Perhaps we better do something even though we have no objective test to distinguish this hate from the imaginary or non-existent."