[…] The morpheme boundaries in an utterance are determined not on the basis of considerations interior to the utterance, but on the basis of comparisons with other utterances. The comparisons are controlled, i.e., we do not merely scan various random utterances, but seek utterances which differ from our original one only in stated portions. The final test is in utterances which are only minimally different from ours.
- Harris (1951), a pag.163