Apparently we still haven't reached the intellectual stage where we're secure enough to admit that in fact we don't know WTF "underlies" reality, if putting it in such as way is even meaningful. I think words like materialism simply represent the point philosophers give up and decide to end the investigations--for a long time "god" served this purpose
^^^^^^^ CB: Engels makes it clear that his meaning for "materialism" is _to_ investigate, as the various sciences do. He declares we never have knowledge of absolute truth , only relative truth, so the search is infinite and the investigation never ends. He definitely doesn't substitute "materialism" for "God" (smile)