Schaffer Fought the Law and the Law Won
A short response to Jonathan Schaffer’s Causation and Laws of Nature: Reductionism
Schaffer argues that both causation and the laws of nature reduce to history. What he means by this is that all descriptions of laws are sufficiently grounded on the history of the world. If a law is to change, then something about the history of the world would have to change. Schaffer uses two analogies to get this point across. First, he says that the laws reduce to history in the same way that a movie reduces to the individual frames; in order to have a different movie, one would need to have different frames. Moreover, describing the frames in their totality describes the movie in its totality. Second, he says that for God to create a universe, He need only to create the space-time components of the universe and the laws fall out for free; He does not need to sew everything together with spooky metaphysical thread. Likewise, describing the entire history of the world will describe the laws of nature .
An Argument in Favor
I agree with Schaffer that the strongest argument in favor of reductionism is the argument from grounding. This hinges largely on the defense of whether modal existents reduce to occurrent existents. Since I am inclined to agree that is sufficient to reduce the laws to history, I will not argue against his (35). I do not see a way out of reductionism if this holds. Schaffer offers three arguments in favor of thinking that modal existents reduce to occurrent existents: (i) it is intrinsically plausible because free-floating modal entities are spook to the max, (ii) it is consistent with Humean recombination, and (iii) it is theoretically useful in ruling out unsubstantiated metaphysical positions .
The Final Assessment
I find Schaffer’s arguments interesting, yet uncompelling. The primary problem is with his seemingly unwavering adherence to Humean recombination. Schaffer essentially argues that laws place unwanted limitations on what is possible. Even if that is the case, then so much the worse for recombination. The purpose of laws, it seems to me, simply is to restrict our notions of what is and is not possible. Specifically, laws constrain what scientists can posit as a constitutive equation that describes the behavior of some material or physical system . Schaffer repeatedly appeals to science: a practice whose purpose is to find out how the natural world is, not how the world could be. In light of this, his complaint that the possibilities are limited seems jarring. But in fact, I do not think that being a primitivist violates Humean recombination. Interestingly enough, while Schaffer complains that theism is what got us into this nomological quandary to begin with, God may be the solution. Imagine a world consisting of two spheres of some mass but are not drawn to each other in accordance with the law of gravity. As it turns out, God is supernaturally holding the two spheres apart from each other. With an omnipotent being in our metaphysical toolbox, recombination does not seem the worse for wear. Even still, I am not convinced that God must intervene to maintain recombination. Imagine that same world with the two spheres but God failed to instantiate the law of gravity. It appears the same outcome is achieved. I am not arguing that this a rebuttal to reductionism; however, I do not think that Schaffer’s arguments go far enough in warranting the position.
- Schaffer, J., Causation and Laws of Nature: Reductionism, in Contemporary debates in philosophy, T. Sider, J. Hawthorne, and D.W. Zimmerman, Editors. 2008, Blackwell Pub.: Malden, MA. p. ix, 404 p.
- Freed, A., Soft solids : a primer to the theoretical mechanics of materials. 2014, New York: Springer. pages cm.
 “If modal existents reduce to occurrent existents, then laws reduce to