Trust: the spiritual impulse after Darwin uncovers the single common basis for both science and religion: faith that we people have in each other. We trust each other to discern and then tell the truth. The fact that science has progressed so far reveals the extent to which that trust is justified. The story of how humankind came to trust itself adequately is philosophical as well as historical. This naturally leads to how our trust can be and must be strengthened for our future.