Medieval Jewish polemics

Recently I was reading Daniel Lasker's Jewish Philosophical Polemics Against Christianity in the Middle Ages.  

1. The Jewish polemic suffers from a couple of basic limitations:

i) As the author notes, their knowledge of Christian theology seems to derive from Catholic missionaries. Popularizers of Christian theology. They apparently lack direct acquaintance with high-level thinkers like Anselm and Aquinas. As a result, the Jewish critics often seem to be attacking a caricature of Christian theology, and they are sometimes unaware of how sophisticated Christian theologians responded to the stock objections they raise.

ii) Both the Jewish critics and their Christian counterparts operate within an Aristotelian framework. In one sense that's a point of strength. It means the Jews are responding to Christian exponents on their own ground. However, for a modern Christian reader, many of their objections lack traction unless you're a Thomist. 

2. Jewish critics attack the virginity in partu on the grounds that two bodies can't occupy the same space at the same time. Given the noninterpenetrability of physical bodies, the process of birth would rupture the hymen. 

Lasker also mentions that patristic theology was divided on the virginity in partu. Tertullian, Origen, and Athanasius denied it while Basil, Gregory of Nyssa, Jerome, Ambrose, and Augustine affirm it, although they failed to provide a philosophical defense. 

I think the Jewish polemic against the virginity in partu raises genuine challenges to that dogma. A Catholic theologian could appeal to a deus ex machina solution to salvage the dogma, but that's ad hoc. 

3. In chap. 4, on the Trinity:

i) One objection goes like this: All things that are many in number have matter (Aristotle). 

That might be effective if we accept the principle. But it's unclear why we should. What about the Mandelbrot set, with infinite self-similar iterations? Yet that's an abstract object. What about a plurality of possible worlds? Yet those are abstract objects. Or plurality within possible worlds. What about a number with an infinite decimal expansion? This objection reflects a poverty of conceptual resources.

ii) Another objection is that whether the three persons, while identical with the divine essence, are something other than the essence. If identical with one essence, how can they be distinguishable? If distinguishable, how can there be one essence? 

a) That's an interesting objection, but it suffers from equivocation. If essential identity is merely equivalent to having or sharing a common substance, then that doesn't entail one-to-one correspondence between person and essence. Although identity implies possession, possession doesn't imply identity.

b) Over and above a common essence, there will need to be some additional distinguishing property, unique to each person.

iii) Another objection is that once Catholic theologians open the door to at least one procession, they can't shut the door to unlimited processions. 

It may be hard for a Catholic theologian to dream up an a priori restriction. Mind you, that objection takes the Nicene paradigm for granted. If, with some modern theologians and many Bible scholars, you deny eternal generation, then that particular objection has no foothold. 

iv) Another objection is that "God's simplicity is infinite, and one infinite can't be larger than another". 

But I don't know why divine simplicity is said to be infinite, so I can't assess that objection. In Cantorian set theory, some actual infinities are greater than other actual infinities. 

v) Another objection is that if the Trinitarian persons correspond to three attributes, plus a common essence, then God is a quaternity rather than a Trinity. 

However, it's an error to think the Trinitarian persons correspond to particular attributes.

vi) Another objection is that if the essence is ungenerated while an attribute corresponding to the person is generated, that introduces composition into the Trinity. 

However, absolute simplicity isn't just a problem for Catholic theologians. It's also a problem of Jewish thinkers like Maimonides. On the face of it, it's nonsensical to say each attribute is interchangeable with every other attribute. That's a familiar conundrum, which is why some theologians reject absolute simplicity. 

vii) Another objection goes like this: the Trinity opens the door to infinite alternation (i.e. distinction between parts, diversity, differentia). The essence has no multiplicity, but the attributes (Persons?) are multiple. The Father and Son emanate the Spirit, but the Spirit doesn't emanate. 

a) But if the "one essence" is, in fact, shorthand for a set of attributes, then there's already multiplicity in the essence. 

b) It's true that saying the Father is ungenerated while the Son and Spirit are generated introduces internal differentiation into the Godhead. We can accept that implication by denying absolute simplicity, or we can reject that implication by denying eternal generation and procession. We can say each person is autotheos. 

c) A traditional rejoinder says these distinctions are not in God's essence but are only distinctions of relation, which doesn't imply plurality in the Godhead. 

However, that only seems to push the question back a step: how are relations connected with the essence? Once again, absolute simplicity generates these kinds of dilemmas, yet both sides of the debate (e.g. Aquinas, Maimonides) subscribed to absolute simplicity. If that's a problem for one side, that's a problem for both sides. 

viii) Another objection goes like this:

If God is one essence and three attributes, no one attribute by itself is God. If each attribute by itself is God, each one would have to be one essence with three attributes, each of which must be one essence with three attributes, and thus, ad infinitum. 

That's an ingenious objection. It suffers from two problems:

a) Although Catholic missionaries may have used three attributes to illustrate the three persons, theologians don't derive the persons from attributes. 

b) This also goes to issues regarding the relationship between God and his attributes. But that's a problem for anyone who endorses absolute simplicity, whether Christian or Jewish.

c) Aquinas fields a similar objection:

The Father produced another divine Person because of his infinite goodness. But the Spirit also has infinite goodness. Therefore, the Spirit should also produce another Person, who'd produce another ad infinitum. 

The Thomistic rejoinder is as follows: the Spirit would produce another Person if his goodness was numerically distinct from the Father's goodness. Since they share the same goodness, differing only in relation, other Persons don't proceed. 

I think that argument requires far more elucidation. In any case, we can block the objection by challenging the assumption that the Father produces the Son and Spirit because of his infinite goodness. We can deny that asymmetrical dependence. We can deny that the existence of the Son and Spirit is contingent on the Father's action or motivation. The essence isn't transmitted from one person to another. 

In fairness, the Jews are responding to Catholic missionaries. My point is that modern Christians aren't bound by that frame of reference. 

ix) They raise a chronological objection about how fathers preexist sons, but that mischaracterizes eternal generation.

x) Another objection is that if the Son is generated, then he's an effect of the generator, who's the cause of his existence. An effect can't be necessary because it is dependent on something else. Hence, God would not be a necessary being. 

a) That's a subtle objection, and I think it has some merit. But we can sidestep the objection by denying the Nicene paradigm (i.e. the Father as the source of the Son and Spirit). 

b) Aquinas fields a similar objection:

Everything that's generated receives its existence from the generator. Yet the divine being is self-subsistent. 

Aquinas counters that since the Father and Son share the same divine existence, one existence can't be distinguished from another. 

That's clever, but appealing to simplicity cuts both ways. Generation requires a distinction between the generator and the effect. 

xi) Another objection is that a father/son relationship is a coordinate relationship involving opposites. But two opposites can't be predicated of the same subject.

a) Two begin with, they're not opposites but just different. Now, it may be "opposite" in the sense of facing each other (literally or figuratively). How two things are positioned in relation to each other. Apposition might be a better term.

b) In addition, it fails to distinguish between contraries and contradictories. 

xii) Here's another objection: If everything predicated of God can't be predicated of the Son, or vice versa, then God has parts. 

It may well be the case that the Trinity is at odds with absolute simplicity. But simplicity is at odds with other things, as well, such as God's freedom. If that's an insuperable problem, we can drop simplicity. 

4. In chap. 5, Lasker reviews a range of Jewish objections to the Incarnation:

i) Since many Jews reject original sin, they reject a premise of the Incarnation. 

Of course, the atonement targets actual sin as well as original sin. 

ii) Even granting universal sin, they think God can forgive apart from sacrifice. However, that raises two issues:

a) What do they think is the purpose of the sacrificial system in the OT?

b) If God can forgive by simple fiat, that's divine voluntarism. But that makes the distinction between good and evil arbitrary. It makes God amoral. Beyond good and evil. 

iii) They consider a divine Incarnation beneath God's dignity. That's similar to the Muslim objection.

But that raises the question of whether divine mercy is beneath God's dignity, inasmuch as the Incarnation is an expression of his mercy. 

In human affairs, we consider it virtuous if someone "lowers" himself to help another in need. Are we better than God? 

iv) They raise a set of related objections: a divine incarnation is incompatible with God's incorporeity, illocality, and immutability. 

That, however, misconstrues the nature of the Incarnation, which doesn't entail a change in God, but a relation between the transcendent Son and a concrete human nature. 

v) Another objection is that a divine Incarnation implies the assumption of accidental properties. Likewise, that it posits potentiality in God. 

In a sense that's true, but in the OT, Yahweh assumes many contingent relations, God as Creator, judge, covenantal lord, &c. So the real point of tension isn't between OT Judaism and the Incarnation but the classical theism espoused by Jewish thinkers like Maimonides. 

vi) Another objection is that a timeless God cannot "become" incarnate, for that implies a change from a prior state. That's a philosophically probing issue. However:

a) It has a parallel with Yahweh "becoming" the Creator of the world. Jews denied the eternity of the world. So the objection is a doubled-edged sword. Jews of that persuasion must allow for a timeless cause of a temporal effect. 

b) The Incarnation is a union or relation. The fact that one side of the relation is temporal doesn't imply the other side of the relation is temporal. 

vii) A cognate objection is that God can't be acted upon, but Jesus was acted upon. 

That, however, fails to differentiate between the two natures. 

viii) Another objection is that restricting the Incarnation to one person of the Godhead is incompatible with absolute simplicity. 

That objection may well hit the target. That, however, is not incompatible with OT theism. Absolute simplicity is a post-biblical development. Indeed, the extreme emphasis on absolute simplicity in Jewish thinkers like Maimonides may be a preemptive strike in calculated reaction to Christian theology. Judaism reinventing itself after the fact. 

ix) Many of these objections miss the mark because they fail to take into consideration the Incarnation as a union of two different natures. That's where the argument is joined.

x) Apropos (ix), one objection is that:

if man were in sin and needed to be redeemed, it would be impossible for God to unite with him. God would have to remove man's sin before such a union could take place. It would be better to say simply that God would forgive man's sin without becoming incarnate.

a) That's ingenuous. However, this is not about removing sin from a sinner, but creating someone without sin. 

b) In addition, sin has two primary components: moral corruption and culpability. The fact that God can make someone without moral corruption doesn't mean God can forgive sin by fiat–any more than God can change the past. There's a categorical difference. Even if God eradicated my moral corruption, I'd still be guilty of past transgression. Removing corruption may prevent future sin, but it doesn't remove the blame for past actions. 

xi) Here's another objection:

According to the Incarnation, the God-man is neither God nor man, but a tertium quid composed of the two natures. 

It's true that the God-man is unique. It's also true that the God-man is a composite. But he's both God and man rather than less than either. It's not a composite in the sense of blending two different natures.

xii) Another objection defined a union in Aristotelian terms as form exemplified in matter. But there's no reason to model the Incarnation on that paradigm.

xiii) An objection to the hypostatic union went like this:

It posits two substances, a God-soul and a God-body. So there's not one incarnation, but two. 

That's an interesting objection. It's true that the Incarnation requires a union between the Son and a human soul as well as a human body. In that respect, the Incarnation is twofold. But that doesn't represent two different events. 

And in any case, the Incarnation does have three elements. It's not inconsistent with the Incarnation to point out that implication. So that does nothing to disprove it.

ix) Another objection is that the Resurrection amounted to reincarnation because there is no soul apart from the body. 

And it's true that the Aristotelian-cum-Thomistic view of the soul makes it difficult to justify the survival of the soul in separation from the body. However, that's a defect of hylomorphism. A Christian isn't committed to Aristotelian or Thomistic anthropology. Cartesian dualism is a better paradigm.

x) Another objection is that if Jesus was God even when he was dead, then God was a dead body. But that fails to distinguish between the Son, the soul, and the body.

xi) Another objection is that if God was in union with a human body, then the body would be immortal–because God is immortal. 

a) That's an interesting objection, but it views the Incarnation in mechanical terms, as if God must communicate his immorality to the body.

b) Moreover, it commits a category mistake: a living body refers to biological life. But God is not alive in that sense. So there's no parity. 

xi) These objections suffer from a poverty of conceptual resources. There are other kinds of unions or relations. In Cartesian dualism, there's a relation or union between two different substances. Or consider how abstract objects in math are exemplified in time and space. Those are better models to work with.