6 - Laws of nature as relations between universals

Summary

The need for universals

It will be assumed from this point onwards that it is not possible to analyse:

(1)It is a law that Fs are Gs

as:

(2)All Fs are Gs.

Nor, it will be assumed, can the Regularity theorist improve upon (2) while still respecting the spirit of the Regularity theory of law.

It is natural, therefore, to consider whether (1) should be analysed as:

(3)It is physically necessary that Fs are Gs

or:

(4)It is logically necessary that Fs are Gs

where (3) is a contingent necessity, stronger than (2) but weaker than (4). My own preference is for (3) rather than (4), but I am not concerned to argue the point at present. But what I do want to argue in this section is that to countenance either (3) or (4), in a form which will mark any advance on (2), involves recognizing the reality of universals.

We are now saying that, for it to be a law that an F is a G, it must be necessary that an F is a G, in some sense of ‘necessary’. But what is the basis in reality, the truth-maker, the ontological ground, of such necessity? I suggest that it can only be found in what it is to be an F and what it is to be a G.

In order to see the force of this contention, consider the class of Fs: a, b, c … Fa necessitates Ga, Fb necessitates Gb … and so on. Now consider the universal proposition: for all x, Fx necessitates Gx. Are we to suppose that this proposition is simply a way of bringing together all the individual necessitations? If we do suppose this, then we seem to have gone back to a form of the Regularity theory. The new version could meet the objection made to the orthodox Regularity theory that no inner necessity is provided for in the individual instantiations of the law. But it will be exposed to many of the other difficulties which we brought against the Regularity theory. For instance, no progress would have been made with the Problem of Induction. In the past, for all x, Fx necessitates Gx. But what good reason can we have to think that this pattern of necessitation will continue?