I recently read Greg Epstein’s book, Good Without God.  Epstein is the humanist chaplain at Harvard University.  I like what Francis Schaeffer said that humanists have their “feet planted in midair.”

In order to substantiate things like morality, personality, and significance from an materialistic perspective, humanists have to borrow from a Christian worldview.  The best “pairing” with an atheistic worldview is nihilism, which is a recognition that there is no objective basis for values or morality.