Mark Hale is an American linguistics professor now teaching at Concordia University in Montreal, Quebec, Canada. He studies the methodology of historical linguistics as well as theoretical linguistics, Indo-European and Austronesian linguistics. He is a prominent figure in these fields. He has published numerous scholarly articles [1] and books [2] on his research. Along with colleague Charles Reiss, he is a proponent of substance-free phonology, the idea that phonetic substance is inaccessible to phonological computation.