Mill, J. S. (1846). Of the limits to the explanation of laws of nature; and of hypotheses. In J. S. Mill, A system of logic, ratiocinative and inductive, being a connected view of the principles of evidence and the methods of scientific investigation (pp. 286-299). New York, NY, US: Harper & Brothers.
http://dx.doi.org/10.1037/11967-028
This chapter discusses the limits to the explanation of laws of nature, and hypotheses. In particular, it looks at the sense in which ultimate laws can be explained; the proper use of scientific hypotheses; plus, legitimate and illegitimate hypotheses. (PsycINFO Database Record (c) 2016 APA, all rights reserved)