In Miracles and the Modern Mind, Norman Geisler summarizes Spinoza’s argument about miracles:

1. Miracles are violations of natural laws.
2. Natural laws are immutable.
3. It is impossible to violate immutable laws.
4. Therefore, miracles are impossible.
(MMM, p.15)

Contrary to Geisler’s interpretation, Spinoza does not argue against the possibility of miracles. Rather, he assumes that miracles do occur, and then argues against defining “miracles” in terms of violations of natural law. In other words, just as Spinoza defines “God” in a non-standard way, he defines “miracle” in a non-standard way.

According to Spinoza (in Theological-Political Treatise, Chapter 6, paragraph 5) , all events must conform to natural laws, so the word “miracle” should be defined not as an event that violates a natural law, but as an event that some person, due to ignorance or the limitations of human minds, is currently unable to explain in terms of natural laws. Thus, we need to formulate Spinoza’s argument a bit differently than Geisler did (above):

Argument for New Definition of “Miracle”

5. If miracles require the violation of a natural law, then miracles are possible only if the violation of a natural law is possible.
6. The violation of a natural law is impossible.
Therefore:
7. If miracles require the violation of a natural law, then miracles are impossible.
8. Miracles are possible.
Therefore:
9. Miracles do not require the violation of a natural law.

This argument from Spinoza in support of a re-definition of the word “miracle” can be adapted, similar to what Geisler has done, in order to support the skeptical view that miracles are impossible. We need to add an additional premise and conclusion to the first half of the above argument:

Argument for the Impossibility of Miracles

5. If miracles require the violation of a natural law, then miracles are possible only if the violation of a natural law is possible.
6. The violation of a natural law is impossible.
Therefore:
7. If miracles require the violation of a natural law, then miracles are impossible.
10. Miracles require the violation of a natural law.
Therefore:
11. Miracles are impossible.

This is not, however, Spinoza’s argument, since he asserts conclusion (9), which is the exact opposite of premise (10) in the argument for the Impossibility of Miracles (hereafter: IOM). Spinoza was arguing that “miracle” should be defined so that such events do not involve a violation of a law of nature, but this argument against miracles is based on the acceptance of just such a definition.

Geisler’s first objection to Spinoza’s argument is that it begs the question. Let’s see if this objection holds up against the IOM argument. Geisler makes six different comments that appear to be related to his “begs the question” charge. I will examine these comments one at a time.

Comment 1: “…anything validly deducible from premises must have been present in those premises from the beginning.” (MMM, p.18)

If I understand Geisler correctly, this is a stunningly stupid comment in support of the charge of begging the question. Geisler’s comment implies that all valid deductive arguments beg the question. But this “proves” way too much. For example, Geisler’s favorite argument for the existence of God, is a deductive version of a cosmological argument. Comment 1 implies that Geisler’s favorite argument for God begs the question. Deductively valid arguments do sometimes beg the question, but many deductively valid arguments do not. This comment provides absolutely no support for Geisler’s charge that Spinoza has committed the fallacy of begging the question.

Comment 2: “…Spinoza has provided no convincing argument..” for “the rationalistic premises” of his argument. (MMM, p.18)

This comment not only fails to support Geisler’s fallacy charge, it actually comes very close to contradicting his objection. In saying that Spinoza has provided no convincing argument for a premise of the IOM argument, Geisler suggests that Spinoza has provided an argument for a controversial premise, but that the argument is defective and falls short of being a solid argument. But if Spinoza has provided an argument for a controversial premise of IOM, then Geisler cannot fairly charge Spinoza with begging the question. The fallacy of begging the question occurs when a controversial premise is simply assumed to be true, without any argument or support being provided for the controversial premise.

If Geisler thinks that Spinoza has given a weak or defective argument for a controversial premise, then Geisler needs to point to that argument and explain why he thinks the argument is weak or defective. Geisler does not do this, so it is actually Geisler who begs the question! Geisler merely asserts that Spinoza has given only unconvincing arguments in support of a basic premise of the IOM argument, without giving any details or explanation or support for this controversial charge.

Comment 3: “Spinoza’s argument…begs the question by defining miracles as impossible to begin with, namely, as a violation of assumed unbreakable natural laws.” (MMM, p.21)

My formulation of the IOM argument does not refer to “unbreakable” natural laws, but the same idea is implied in premise (6):

6. The violation of a natural law is impossible.

Spinoza does not define miracles in terms of violations of natural law. In fact, he argues that it is mistaken to define miracles that way. However, the IOM argument is not really Spinoza’s argument, but is derived from borrowing part of Spinoza’s argument and adding a premise that Spinoza would himself reject:

10. Miracles require the violation of a natural law.

Since Spinoza argues against (10), I assume that he does not also argue in favor of (10). So, if Geisler had doubts about (10), he would be partially correct to say that Spinoza begged the question by failing to provide an argument for the definition of miracles presupposed by (10). However, Geisler does not object to defining miracles as involving a violation of a law of nature. So, the question begging that Geisler thinks occurred, relates to premise (6), not premise (10).

Premise (6), however, does not put forward a definition of “miracle”, and so Geisler is wrong in asserting that a question-begging definition of miracle is being assumed or asserted in the IOM argument. Geisler is making the same mistake here as with Comment 1. It is the combination of (6) and (10) that implies the impossibility of miracles, but neither premise (6) nor premise (10) assumes impossibility of miracles. Thus, neither (6) nor (10) begs the question by assuming what needs to be proven.

Premise (6) is, however, a controversial claim, so (6) needs to be supported by further arguments or reasons in order for the IOM argument to avoid the charge of begging the question.

To be continued…