Definition: The beginning is that which precedes everything by reason of some priority.
Clarification and division: Principle or beginning can be considered in many ways, as shown in this Art: thus, the principle called the end is the principle that initiates the beginning and the beginning is the principle meant for the end. Hence, there is a being that is both a beginning and an end in itself, in one simple natural essence of both beginning and end. Now such a principle is the supreme beginning because if it were not essentially and naturally a beginning and an end, it would be an accidental beginning and end. And hence it would follow that the beginning and the end would be greater in accident and lesser in essence or substance, which is an ultimately untenable impossibility. Beneath this supreme principle, other principles stand in causal order, for instance the end in things here below is the principle that moves the efficient cause to act, and the efficient cause is the principle that moves form to inform its matter. And as form is the principle that gives being to matter by informing it, so is matter a principle, given that substantial being consists of active form and passive matter. Now there are other, accidental principles such as time, quantity, quality, relation and the other predicates without which form and matter could never constitute substances, generation and corruption could never proceed and matter could never be a principle that resists its form.
This is how knowledge of the conditions of supreme and lesser principles directs the artist to discover means for concluding about any question involving principle. For the sake of this knowledge, principle must be included in this Art with the other principles.
Clearly, if there were no such principle as described above, no natural thing could ever exist, since whatever exists is either a cause or an effect.
Nature: The perfection or fullness of principle consists in the originator, originated and the act of originating.
Hence, in the supremely perfect principle these correlatives are distinctly, without confusion, one infinite essence and nature, whereas in lesser things they are finite.