Charles Lyell, Historian of Time's Cycle - Time's Arrow, Time's Cycle: Myth and Metaphor in the Discovery of Geological Time - page 128

D'Orbigny and Agassiz had no beef with Lyell about method— they all
agreed that inquiry must begin with present processes and that modern causes
must be entirely exhausted before any extinct or exotic process be
considered. They differed in their judgment about the world's response to this
common method. Lyell believed that modern causes would suffice to explain
everything about the past. Agassiz and d'Orbigny viewed actualism as a
method of subtraction for identifying the unchanging substrate of modern
causes, thereby highlighting the phenomena that required special explanation
by processes outside the current range.
Nonetheless, d'Orbigny also admitted that modern causes would greatly aid
the understanding of past catastrophes—for paroxysms may be caused by
modern forces greatly magnified in degree. D'Orbigny argued, for example,
that any change in topography during an earthquake "is, for us, on a small
scale, and with effect much less marked, the same phenomenon as one of the
great and general perturbations to which we attribute the end of each
geological epoch" (1849-1852, II, 833-834).
All agreed, therefore, that the most valuable of all possible tools for
interpreting the past would be a proper catalogue of the variety, range, rates,
and extent of modern causes. Lyell had provided the finest compendium ever
assembled. I believe that this elaborately detailed catalogue, above all else,
won for Lyell the bounteous praise that catastrophists like Agassiz gratefully
accorded.
Thus, the real debate between Lyell and the catastrophists was a complex
argument of substance among men who agreed about methods of inquiry.
Lyell's substantive uniformities of rate and state commingle to form a
powerful vision of a dynamic earth, constantly in motion but never changing
in general appearance or complexity—a stately earth playing a modest
portion of all its acts all the time, not concentrating single modes of change
into global episodes, and not alternating worldwide periods of tumult and
quiescence, uplift and erosion.
Lyell's attitude to James Hutton illustrates the mixture of his substantive
uniformities. Lyell praised Hutton for his nondirec-