Perceive the moon, changing in phases. We say the moon is large when much of its surface reflects light and small when it reflects light upon less of its surface. The mass of the moon is constant no matter the angular phase of light reflecting off its surface. All living things pass from non-existence, through being. All perception of reality exists only within these transient minds. As each transient perception passes, somehow the universe remains. The moon passes through its phases. Transient perception has phases, also.