In 2000, a colloquium entitled Borneo as the Homeland of Malay was held in Malaysia. The participants, who included the leading experts in the field, seemed to agree that the title of the colloquium was appropriate, and that the homeland of Malay was indeed in Borneo. This paper points out a few problematic aspects of this hypothesis. One problem is the inability, or reluctance, to distinguish between Malay (a language) and Malayic (a group of related languages). The distinction may not be very consequential for the reconstruction of Proto-Malayic, but it is of crucial importance for determining the homeland. After all, there is no logical reason why the place where Malay first arose as a language should be identical to the place where its ancestor originated.

A more serious problem, however, lies with the main argument used to support the Borneo homeland hypothesis, namely diversity. It has long been a rule of thumb for historical linguists that the area where a language-or group of related languages-exhibits the greatest diversity is the most likely location of the original homeland of the language (or proto-language) in question. Nonetheless, this criterion should not be used arbitrarily. Specifically, the diversity argument is only valid when the diversity in question is the result of internal language change. Contact-induced change can be much more rapid than internal change; in fact, it may cause the emergence of a new isolect within as little as one generation. Therefore, diversity brought about by language contact cannot be used as evidence for determining the homeland of a language.

This paper suggests that much of the linguistic diversity among the so-called Malayic isolects of Borneo is due to language contact, and therefore may not constitute good evidence for the Borneo as the Homeland of Malay hypothesis. It is, at best, poor argument; in the case of substrate phenomena, it even constitutes counter-evidence.