Charles Lyell (born November 14, 1797, † February 22, 1875)
The geologist Charles Lyell is considered the most important co-founder and representative of timeliness principle, Under the influence of his father, the eponymous botanist Charles Lyell, he initially took a law degree, but nevertheless dealt intensively with botany, geology and the general natural sciences. From 1831 Charles Lyell then took over the chair of geology at the University of London.
The actuality principle (also actualism or Gleichförmigkeitsprinzip called) is based on the central assumption that the natural laws valid today, even in the past, were valid. Ergo: Certain processes and processes today take place under the same conditions (laws of nature) as millions of years ago. From this, concrete conclusions about the past can be drawn by observing the present alone. For the manifestations resulting from the unchanging laws of nature cause similar / identical products. By means of a simple example this analogy conclusion shall be clarified briefly:
We can observe how islands in the oceans, along the continental plates, develop due to volcanic activity. The actuality principle says now, if we can observe the island formation by volcanoes nowadays, then formed in the same way already several million years ago islands.
Incidentally, the idea of actualism does not originate from Charles Lyell himself, but was already a few years ago by James Hutton (read in Theory of the Earth: With Proofs and Illustrations, 1795). Lyell further developed the concept and made with his publications for the announcement.
Charles Lyell's observations and assumptions also influenced Charles Darwin, who took the book 'Principles of Geology' on his world tour with the HMS Beagle and studied intensively. Darwin was able to verify Lyell's views, so he sought contact with Lyell after his voyage. This resulted in a friendly relationship with lively, scientific exchange. In the end, actualism also found its way into the theory of evolutionDarwin felt that his assumptions confirmed that the evolutionary factors (gene drift, mutation, recombination, selection) must have been applied much earlier.