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A MEMOIR ON ABSTRACT GEOMETRY.
[413
22. There is no meaning in aggregating a relation with itself; such aggregation
only occurs accidentally when two relations aggregated together become one and the
same relation ; and the aggregate of a relation with itself is nothing else than the
original relation.
23. A onefold relation is not an aggregate, but is its own sole constituent ; a
more than onefold relation may always be considered as an aggregate of two or more
constituent relations. The constituent relations determine, they in fact constitute, the
aggregate relation ; but the aggregate relation does not in any wise determine the con
stituent relations. Any relation implied in a given relation may be considered as a
constituent of such given relation.
24. The aggregate of a ¿-fold and a /-fold relation is in general and at most a
(& + /)fold relation; when it is a (& + /)fold relation, the constituent relations are
independent, but otherwise, viz. if the aggregate relation is, or has for factor, a less
than (le + /)fold equation, the constituent relations are dependent or interconnected.
25. Passing from relations to loci, we may say that the composition of relations
corresponds to the congregation of loci, and the aggregation of relations to the inter
section of loci.
26. For, first, the locus (if any) corresponding to a given composite relation is
the congregate of the loci corresponding to the several prime factors of the given
relation, the locus corresponding to a single factor being taken once, and the locus
corresponding to a multiple factor being taken a number of times equal to the
multiplicity of the factor.
27. And, secondly, the locus (if any) corresponding to a given aggregate relation
is the locus common to and contained in each of the loci corresponding to the several
constituent relations respectively ; or, what is the same thing, it is the intersection of
these several loci.
28. It may be remarked that a &-fold locus and a /-fold locus where k + / > m
(or where the aggregate relation is more than m-fold) have not in general any common
locus.
29. Any onefold relation implied in a given &-fold relation is said to be in
involution with the &-fold relation, and so in a system of onefold relations, if any
relation be implied in the other relations, or, what is the same thing, in the relation
aggregated of the other relations, then the system is said to be in involution ; a system
not in involution is said to be asyzygetic.
30. Consider a given &-fold relation, and, in conjunction therewith, a system of any
number of onefold relations each implied in the given &-fold relation. We may omit
from the system any relation implied in the remaining relations, and so successively
until we arrive at an asyzygetic system. Consider now any other onefold relation
implied in the given &-fold relation ; this is either implied in the system of onefold
relations, and it is then to be rejected, or if it is not implied in the system, it is to