Sorites

so·ri·tes (sә-rī'têz, sô-), n. [L., from Gr. swrei`ths (sc.
syllogismo`s), properly, heaped up (hence, a heap of
syllogisms), fr. swro`s a heap.] (Logic)
An abridged form of stating of syllogisms in a series of
propositions so arranged that the predicate of each one that
precedes forms the subject of each one that follows, and the
conclusion unites the subject of the first proposition with
the predicate of the last proposition, as in following
example;
[1913 Webster]

The soul is a thinking agent;
A thinking agent can not be severed into parts;
That which can not be severed can not be destroyed;
Therefore the soul can not be destroyed.
[1913 Webster]

For example, if one argues that a given number of grains of sand does not make a heap and that an additional grain does not either, then to conclude that no additional amount of sand will make a heap is to construct a sorites argument.