"Is [this theory]
The book that popularized this theory includes a detailed description of how the stones in two obelisks were rotated differently by a 1783 earthquake in Calabria. That book about this theory accounted for regional differences between species by proposing that they come from the "creative energy" of "centres, or foci, of creation." Stephen Jay Gould's first scientific paper advocates a strongly modified form of this theory and is titled "Is [this theory] Necessary?" The first proponent of this theory collaborated with John Playfair to calculate the extent of deep (*) time. This theory absorbed a modified form of Anton Moro's plutonism to replace Abraham Gottlob Werner's Neptunism. This theory, which is opposed to Georges Cuvier's catastrophism, was first proposed by James Hutton. For 10 points, name this theory that was summarized as "the present is the key to the past" by its popularizer, the geologist Charles Lyell.
The book that popularized this theory includes a detailed description of how the stones in two obelisks were rotated differently by a 1783 earthquake in Calabria.
uniformitarianism [or gradualism; accept "Is Uniformitarianism Necessary?"]