Things that are said to be living are those that move themselves. Those things which cannot by their very nature are not living. Next, living is essential in that it is in a thing’s nature to live or be alive, rather than as an accident just merely existing.
There are levels if you will, of life. Plants contain a sort of life of cell division, growth, reproduction. Further, animals contain the same life as plants but additionally have appetite, sentience, and instinct. Humans have both of these levels and additionally possess the rational life of feeling, will, understanding, abstract, objection, etc. These, as universals, are the essences of the things. Now, these are also levels of perfection or change.
The prime mover, God, is pure act, is perfect, and is not in change but always is and so all life belongs to God in His very essence. God’s life, as we have been progressing to see, is His very essence which is in turn made up of these different names – knowledge, love, goodness, etc. But they are all Him, all the time, perfectly present and are not separate as they all simultaneously make up his essence.
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