The Unity That Is Not Numberacross the parts · on divine simplicity

His unity is not an additional notion to His essence, but His essence is one. He is one with a unity that admits of no composition whatsoever; He is one as no other one is one. after Guide I:57; Mishneh Torah, Hil. Yesodei haTorah 1:7

The Shema declares the Lord is one. Maimonides treats this not as a count but as a denial. The one of arithmetic is the one of enumeration; one apple, one army, one God if taken in this sense — the first member of a list. The first chapters of the Mishneh Torah and the heart of Guide I (I:51–57) argue that this is precisely the wrong reading. God's oneness is not a quantity. It is the absolute absence of composition.

What composition would mean

Anything composite is, in being analysed, found to consist of parts: a body of its organs, a soul of its faculties, even a definition of its genus and differentia. Each part is, in some sense, prior to the whole; the whole depends on the parts for its existence. To say that God has parts, in any sense, is therefore to make Him dependent on something prior. This Maimonides cannot accept.

But the threat of composition arises in more subtle places than the obvious one of body. If God has an attribute — wisdom, will, power — then God plus the attribute are two things named once. The attribute is in God as in a subject; God is the substrate, the attribute is the predicate. Two metaphysical roles, therefore two things. Even if the things are inseparable in fact, they are distinct in account.

Whoever believes that God is one and that He has many attributes declares the unity with his lips and assumes plurality in his thought. Guide I:50

The diagnosis is severe. It is not enough to say God is one; one must mean it, and meaning it requires a metaphysics of attributes that the ordinary monotheist has not yet acquired.

Identity of essence and existence

Maimonides' positive (or as-positive-as-the-via-negativa-allows) formulation is borrowed from his Falsafa sources: in God, essence and existence are identical. In every creature, that it is and what it is are distinct — Socrates is a man, and Socrates exists, and these two are different facts. In God they coincide. There is no answer to what is He? distinct from the answer to is He?. The essence simply is the existing.

This is the doctrine of absolute simplicity, and it is the metaphysical engine behind every other Maimonidean position. It generates the via negativa — there is nothing of His to predicate. It generates the lexicon of homonyms — body language could not refer to such a simplicity. It constrains the account of providence and the account of cosmology.

What it costs. The cost is that God becomes, in important respects, opaque to us. The personal God of liturgy — the one who hears, who is grieved, who relents — cannot be the simple God of metaphysics, except through the doctrine of equivocal predication that Maimonides has spent the Guide constructing. Many readers, then and since, have found the equation between the two too thin to support the weight placed on it. The Guide's task is to make the equation bearable; whether it succeeds is the perennial question.

What the thread closes

This is the spine. Via Negativa, Homonyms, Aristotle in a Cave, The Storm and Its Voice, and Reasons for the Mitzvot are all consequences of, or are constrained by, the doctrine of absolute simplicity. Read in isolation any of them seems an episodic puzzle. Read against the unity- argument, they are a single position carefully held across a long book.

The perplexed reader, on this account, is the one who has begun to see the position but not yet seen how each part of it follows from the next. The Guide is the recovery of that seeing.