Mason observes that while at first Spinoza's views on modality seem completely straightforward a second look shows them to be confusing even contradictory. Mason speculates about what Spinoza must have had in mind that would bring consistency to his statements and the result is startling in the contrast it presents to our modern way of looking at logic and the world at large. Nor is it self-evident that Spinoza was wrong and we are right!

The apparent simplicity of Spinoza's modal system is based on his repeated and adamant assertions of a completely determined and universal necessity. But there are four areas of complications.

1. His system requires essence, but essence implies accidents, and accidents imply contingency.
2. Spinoza himself seems to suggest that some forms of contingency exist, that man, for example, does not exist by necessity.
3. This view of man contrasts with his view of geometric figures, although there does not seem to be any pertinent distinction between man and geometric figures that would account for this different treatment.
4. Spinoza, after ruling out possible worlds, seems elsewhere to let possibility in by the back door.

But Mason notes that Spinoza was speaking about things rather than propositions in his work. He was not concerned with the relations between subjects and predicates, nor would he have accepted the notion of partial, relative, or hypothetical necessity. He did not have any place in his thought for a distinction between what can be conceived as possible ('logical possibility', in our customary terminology) and what is causally or practically possible. Likewise, necessity applies to things rather than truths. Spinoza is concerned not with what must be the case, but with what must be; the 'must' of necessity is not what must be true, but what must be caused or explained. And the contrary to 'necessary', therefore, is 'uncaused' or 'accidental'. The argument against contingency is that everything must have a cause.

This explains Spinoza's view of individuals. Although persons are not the cause of their own existence, their existence does have a cause, even if the chain of causes is indefinitely long. In this sense, therefore, individuals are necessary, while they are not necessary in the sense that from the order of nature we could conclude the any given individual must exist.

But this is a weak version of necessity. What was Spinoza's thought on genuine necessity? Mason observes that Spinoza never answered this question. But Mason himself suggests what Spinoza's answer would have had to be in order to remain consistent with his system: the facts of geometry, for instance, would be seen as necessary because they were caused by other facts about the world considered as extension, and these other facts would be explainable likewise, until we reached some facts that would be self-caused.

This approach to necessity gets Spinoza out of seeming difficulties concerning essence, too. His intention seems to be (for he is not explicit about this, either) to say that the essence of something is what is constitutive of it, what makes it what it is. And so here again, the fundamental notion is not essence in itself or necessary truth, but causation and explanation. What Spinoza does, in effect, is to reverse our notion of the relation between essence and necessity: where we might like to say that truths are necessary because of what they say about the essential nature of the world, Spinoza would rather say that essences are what they are in virtue of their necessary relationship to their causes.

Mason shows that the four apparent contradictions in Spinoza's idea of modality are resolved by these unfamiliar but coherent positions. And he also considers their broader implications. Spinoza seems to have everything backwards. We see necessity as requiring some explanation, where Spinoza sees contingency as the problem. We are cautious about speaking of the necessity of things, while Spinoza takes virtually no notice at all of the necessity of propositions. We tend to define necessity and possibility in terms of one another, which is completely foreign to Spinoza's system.

Then is Spinoza just wrong? Mason believes that this would be harder to prove than makes us comfortable. Yet if Spinoza is right, the implication is that the only way to find out what is possible is to see what can happen in the world, not to think about it. And this would radically undermine a good deal of the formulation of modern philosophy.

Contents

Index