Permutations
of the Multilinear Stratigraphic Sequence: Nature, Mathematics and
Consequences
The phrase "permutations
of the multilinear stratigraphic sequence" was introduced in
1984 by Edward C. Harris . Since then the notion has entered into
the collective awareness of stratigraphers, though no author has so
far been willing to confront permutations head on. Harris noted that
the notion was "not acceptable for publication in 1982"
And less than a decade ago (1993) Triggs elegantly understated that
when "a single deposit is held constant and other deposits are
moved in relation to it, the permutations ... ... can be on an exponential
scale for even a small site."
This contribution discusses the nature of "permutations of the
multilinear stratigraphic sequence" and suggests ways of calculating
those permutations. It will be necessary to look at the mathematics
appertaining to the stratigraphic sequence in some detail to understand
how permutations may be calculated. Then, in conclusion, to discuss
the consequences of this explicite knowledge about the permutations
of the mulilinear stratigraphic sequence. For the phasing of a site
is closely related to the reduction of the possible permutations of
a stratigraphic sequence to a number less than the maximum. This takes
place under inclusion of non-stratigraphic criteria such as finds-dating,
dendrochronology etc. Phasing does not change the relationships of
contexts on a common lines of the sequence. Rather, is fixes the relationships
to each other in time, of contexts on different lines, whose relationships
cannot be ascertained on purely stratigraphic evidence, thereby assigning
them to phases and periods. The reduction of the permutations to less
than the maximum therefore has a direct relationship with the interpretation
of a site and with the definition of phase- or period-interfaces.
At its simplest, accepting the maximum permutations would essentially
be the same as admitting that the site is unphasable. Conversely,
a single possible permutation would indicate a perfectly phased site
where everything fits into place. The analysis of permutations might
therefore not only be an archaeological tool which can facilitate
the phasing of a site but also an analytical one with which the criteria
used in phasing and thus interpreting any site can be critically examined.