Uniformitarianism
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Uniformitarianism is a principle in science and the philosophy of science. It is, essentially, the assumption that natural law has always operated as it operates at present. Although an assumption, it is considered a very good and reasonable assumption, and certainly produces theories which are self-consistent, plausible and that explain observed evidence well. However, its successes are often ignored as it leads to conclusions that are disliked by certain groups, and these groups will do anything to discredit it as a useful tool for the study of the natural world.
The methodological naturalism of modern science is made much more useful by this principle. The principle of uniformitarianism allows scientists, such as geologists, to study the past without actually having been there to directly observe it.
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[edit] History
The principle of uniformitarianism was first formulated by Charles Lyell in his seminal work, Principles of Geology published in 1830. This was built on the insight of "deep time" propounded by James Hutton to explain geological processes. However, the term 'uniformitarianism' was not coined by Lyell but by the Cambridge academic William Whewell who called Lyell a uniformitarian in contrast to his own catastrophism — catastrophism, of course, being a euphemism for the Biblical flood. The ensuing arguments between deep-time scientists and Biblical literalists brought the term catastrophism into disrepute. For a long time the idea of uniformity of physical processes and uniformity of geological processes and their rate of action was the accepted model for uniformitarianism; however, as more geological evidence was accrued it became obvious that there have been both major and minor catastrophic occurrences in the Earth's history which have left their mark in both the geological and biological records. These have been entirely natural, albeit rare, events which neither upset the principle of uniformity of physical processes nor support the Biblical account of a global flood.
[edit] Criticism of uniformitarianism
[edit] By young-Earth creationists
Uniformitarianism has come under much criticism from young Earth creationists and such types, who posit that natural law has changed over time; specifically, that it has been altered by God for the purpose of resolving some messy inconsistencies of observed phenomena with the Honest-To-God TruthTM found in Genesis.
An example is the challenge against radiocarbon dating taken up by the people of the RATE committee which in condensed form follows this format:
- Scientist: By measuring the decay of carbon-14 in organic material, one can ascribe dates to fossils up to 60,000 years old.
- Creationist: That contradicts the biblical account of creation, so it's false.
- Scientist: But the radiocarbon dates line up perfectly with dates we know from other sources back 4,000 years.
- Creationist: You're working from the false premise of uniformitarianism. The truth is that the rate of radioactive decay changed during the Great Flood, so hundreds of thousands of years' worth of radioactive decay happened in a few days.[1]
- Scientist: Er, that level of radiation would have generated enough heat to vaporize the Earth and nuke Noah.
- Creationist: Oh, ye of little faith. Do you not see that God also expanded the universe at the same time to keep
everythingonly the radioactive elements cool?[2]
(We told you it was messy.)
[edit] Other criticisms
Another criticism takes the milder approach of positing that it is a very big step to assume that in the few thousand years humans have been observing natural law, they have captured with any accuracy the principles by which the universe has operated for some 13 billion years.
This shortcoming is illustrated in a story about Charles Babbage. In order to make a point about miracles, Babbage would set his Difference Engine to wind from 2 to 4 to 6 to 8 to 10 to 117; his point being that a supposed "miracle" (the departure from an arithmetic progression) might only be the operation of some higher natural law hitherto unknown (i.e., God did not need to meddle with the gears in the Difference Engine for the departure to happen).
[edit] Answering criticisms
These criticisms may be answered by pointing out that a large number of predictions based on uniformitarianism (in astronomy, for example) have turned out to be very accurate, and thus there is absolutely no harm in assuming uniformity.
In addition to the fact that uniformitarianism as an assumption works, its premise is also a reasonable one when we shave its beard. To postulate that mechanisms and rates were different in the past would require a researcher to determine not only what those mechanisms were but why they are different to today. Creationists will often claim that radioactive decay was different during "Creation Week", thus fudging the numbers to come up with any age they like, although not one shows any evidence of why they were faster or how the rates changed. Not to mention the side effects of extremely enhanced rates, such as where they claim millions of years radioactivity could happen in days, releasing enough energy to blow apart the planet (as mentioned above). On the other hand, the structure of rock strata, cratering and weathering and many other factors that scientists have looked at support uniformitarianism. Creationists are left with their one main handy escape hatch: Goddidit!
Modern uniformitarianism, unlike conceptions that existed in earlier times, accepts that exceptional and extreme events, unknown in the time frame of humans, may have occurred in the past. Examples include the Messinian Salinity Crises (during which the Mediterranean Sea closed and almost completely dried up), the almost unimaginably extreme volcanism of the American West during the early Cenozoic, and the astoundingly huge floods emanating from glacial lakes during the Ice Ages. However, Occam's Razor rules, and such events are to be invoked only when no more mundane ("uniform") explanation covers the observed facts.