Uniformitarianism
Uniformitarianism
Uniformitarianism is commonly oversimplified
where stated in geological textbooks as ‘‘the present
is a guide to interpreting the past’’ (or words to that
effect). This explanation, however, is not correct about
the true meaning of uniformitarianism. In order to
understand uniformitarianism, one must examine its
roots in the Enlightenment era (c. 1750–1850) and how
the term has been distorted in meaning since that time.
Geology is an historical science, yet the phenomena and processes studied by geologists operated
under non-historical natural systems that are independent of the time in which they operated. It is clear
from the insights of one of geology’s founding fathers
of the Enlightenment era, James Hutton (1726–1797),
that he understood this fact very well. In Theory of the
Earth (1795), he stated: ‘‘In examining things present,
we have data from which to reason with regard to
what has been; and, from what has actually been, we
have data for concluding with regard to that which is
to happen thereafter.’’ With his book, Hutton popularized the notion of ‘‘examining things present. . .with
regard to what has been,’’ but gave the concept no
specific name. Hutton did not use the term uniformitarianism and used the word ‘‘uniformity’’ only rarely.
Charles Lyell (1797–1875), one of geology’s founding fathers from later in the Enlightenment era, wrote
about the subject matter of uniformitarianism (but did
not use that specific term) in his widely read text,
Principles of Geology (1830). Partly in response to strident criticism that his notions about geology did not
conform to Biblical edicts about supernatural catastrophic events, Lyell developed a much more radical
and extreme view of the subject matter of the ‘‘uniformity of nature.’’ Careful reading of what Lyell laid out in
his discussion of the ‘‘uniformity of nature’’ shows that
he embraced both the concept of Hutton, which can be
summarized as a uniformity of known causes or processes throughout time, and his own separate view that
there must be a uniformity of process rates. The latter,
more radical aspect of Lyell’s ‘‘uniformity of nature’’
was intended to be a statement of general principle to
counter the catastrophist interpretations of the past set
forth by geologists of the day who were more inclined to
look to the scriptures for their geological interpretations. In Lyell’s view, a strong notion of uniformity of
rates precluded divine (i.e., catastrophic) intervention.
In 1837, the name uniformitarianism was coined
by William Whewell (1794–1866) as a term meant to
convey Hutton’s sense of order and regularity in the
operation of nature and Lyell’s sense that there was a
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uniformity of rates of geological processes through
time. It is Whewell’s definition that became the most
common definition of uniformitarianism.
Lyell’s work was influential, and he succeeded in
imbuing generations of geologists with the notion of a
dual foundation for ‘‘uniformity of nature.’’ This dual
foundation encompassed both uniformity of causes and
uniformity of intensity. The former view is more commonly called actualism, and the latter, gradualism. In
large part, the presence of Lyell’s strongly defended
gradualism succeeded in freeing nineteenth century
geology from the firm grasp of Biblical preconception
and allowed it to develop as a legitimate science.
One of the most elegant statements about actualism was made by John Playfair in his book,
Illustrations of the Huttonian Theory (1802). He said:
‘‘Amid all the revolutions of the globe the economy of
Nature has been uniform, and her laws are the only
things that have resisted the general movement. The
rivers and the rocks, the seas, and the continents have
been changed in all their parts; but the laws which
describe those changes, and the rules to which they
are subject, have remained invariably the same.’’
Actualism is not unique to geology, as it is really a
basic and broad scientific concept of many fields. Even
though Playfair mentions laws, it is, of course, nature
itself that is constant, not laws that have been written
by people in order to try to predict nature.
The other side of Lyell’s ‘‘uniformity of nature,’’
i.e., gradualism, has no such elegant prose behind it. It
has been referred to in inglorious terms by some of the
leading minds of our time as ‘‘false and stifling to
hypothesis formation,’’ ‘‘a blatant lie,’’ and ‘‘a superfluous term. . .best confined to the past history of geology.’’ In other words, gradualism is no longer considered
a valid idea.
Because uniformitarianism has this historical
component of uniformity of process rates (i.e., gradualism), many writers have advocated its elimination
from the geological vocabulary. Others argue that
should be retained, but with careful notation about
its historical meaning. Some writers ignore this historical debate and continue to tout the term uniformitarianism as the most basic principle of geology. The
range of misguided meanings of this term from some
recent geology texts includes definitions that span the
gamut from something near the nineteenth century
meaning to the assumption that the Earth is very old,
to the logical method of geologic investigation.
Careful analysis of geological texts and recent scientific articles shows that there are at least 12 basic
fallacies about uniformitarianism, (such as those
GA LE E NC YC L OPE D IA OF SC IE N CE 4
1. Uniformitarianism is unique to geology.
2. Uniformitarianism was first discussed by James
Hutton.
3. Uniformitarianism was named by Lyell, who
gave us its modern meaning.
4. Uniformitarianism is the same as actualism, and
should be re-named actualism.
5. Uniformitarianism holds that only processes
that are currently active could have occurred in
the geologic past.
6. Uniformitarianism holds that rates and intensities
of geologic processes are constant through time.
7. Uniformitarianism holds that only non-catastrophic, or gradual processes have operated
during geologic time.
8. Uniformitarianism holds that Earth’s conditions have changed little over geologic time.
9. Uniformitarianism holds that Earth is very old.
10. Uniformitarianism is a testable hypothesis, theory,
or law.
11. Uniformitarianism applies to the past only as
far back as present conditions have existed on
Earth’s surface.
12. Uniformitarianism holds only that the governing laws of nature are constant through space
and geologic time.
Through historical analysis of uniformitarianism,
one is able to see how these twelve common conceptions are false and misleading. Most scientists argue
that uniformitarianism should be kept in its proper
historical perspective in the future, and that a more
specific term like actualism might supplant uniformitarianism in places where the word is meant to convey
strictly the modern concept of uniformity of causes.
See also Stratigraphy (archaeology); Stratigraphy.
Resources
PERIODICALS
Gould, S.J. ‘‘Is Uniformitarianism Necessary?’’ American
Journal of Science. 263 (1965): 223–28.
Gould, S.J. ‘‘Reply to C.R. Longwell’s Criticism of
‘Is Uniformitarianism Necessary?’’’ American Journal
of Science. 263 (1965): 919–21.
Shea, J.H. ‘‘Twelve Fallacies of Uniformitarianism.’’
Geology. (September, 1982): 457.
David T. King, Jr.
G A LE EN CY C LO PE DI A O F S CI E NC E 4
Units and standards
A unit of measurement is some specific quantity
that has been chosen as the standard against which
other measurements of the same kind are made. For
example, the meter (m) is the unit of measurement for
length in the metric system. When an object is said to
be 4 m long, that means that the object is four times as
long as the unit standard (1 m).
The term standard refers to the physical object on
which the unit of measurement is based. For example, for
many years the standard used in measuring length in the
metric system was the distance between two scratches on
a platinum-iridium bar kept at the Bureau of Standards
in Sèvres, France. A standard serves as a model against
which other measuring devices of the same kind are
made. The meter stick in a classroom or home is thought
to be exactly 1 m long because it was made from a
permanent model kept at the manufacturing plant that
was originally copied from the standard meter in France.
All measurements consist of two parts: a scalar
(numerical) quantity and the unit designation. In the
measurement 8.5 m, the scalar quantity is 8.5 and the
unit designation is meters.
History
The need for units and standards developed at a
point in human history when people needed to know
how much of something they were buying, selling, or
exchanging. A farmer might want to sell a bushel of
wheat, for example, for 10 dollars, but he or she could
do so only if the unit bushel was known to potential
buyers. Furthermore, the unit bushel had to have the
same meaning for everyone who used the term.
The measuring system that most Americans know
best is the British system, with units including the foot,
yard, second, pound, and gallon. The British system
grew up informally and in a disorganized way over
many centuries. The first units of measurement probably came into use shortly after 1215. These units were
tied to easily obtained or produced standards. The yard,
for example, was defined as the distance from King
Henry II’s nose to the thumb of his outstretched hand.
The British system of measurement consists of a
complex, irrational collection of units whose only
advantage is its familiarity. As an example of the problems it poses, the British system has three different units
known as the quart. These are the British quart, the
United States dry quart, and the United States liquid
quart. The exact size of each of these quarts differs.
In addition, a number of different units are in use
for specific purposes. Among the units of volume in
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Units and standards
explained by University of Wisconsin Geology
Professor James H. Shea), which are perpetuated by
some writers. These are: