I've been looking at Lewis recently, due to a summer reading group. I might post about our fascinating discussion of Lewis on chances at some point, but thinking about the Lewis view of laws of nature brought to my mind a thought experiment which I believe I first heard from Lewis and which I always found quite amusing (some will doubtless take this as proof that I am a horrible judge of what's amusing).
Apparently this comes from Tooley. Imagine that it is true that all of the fruit in Smith's garden is apples. Further, this situation is quite robust. Plant an orange tree in Smith's garden, and it either produces apples, or it produces no fruit. Try to bring a banana into the garden, and it turns into an apple. Lemons simply vanish upon approach. Grapes are repelled by an irresistable force. Suppose that all efforts to find an underlying cause or mechanism for the behavior of Smith's garden are unsuccessful, but that while the means are miscellaneous, the effect, that no non-apple fruit is ever present in the garden, is exceptionless. I'm not sure what Tooley does with the thought experiment, but what I'd like to know about the case is this. Is there any point at which it becomes reasonable to conclude that "all of the fruit in Smith's garden is apples" is a fundamental, basic law of nature?