The chain of being is composed of a great number of hierarchical links, from the most basic and foundational elements up through the very highest perfection, in other words, God. God, and beneath him, the angels, both existing wholly in spirit form, sit at the top of the chain. Earthly flesh is fallible and ever-changing: mutable. Spirit, however, is unchanging and permanent. This sense of permanence is crucial to understanding this conception of reality. It is generally impossible to change the position of an object in the hierarchy. (One exception might be in the realm of alchemy, where alchemists attempted to transmute base elements, such as lead, into higher elements, either silver, or, more often, gold—- the highest element.)