In examining a possible analogy between the process of decreolization and the process of second language learning in a natural environment, speculations are made here to account for the similarities between the linguistic development exhibited in decreolization and second language learning in terms of extra-linguistic factors which seem to affect the degree to which the learner acculturates toward the ‘model’ language group. It is claimed that extra-linguistic factors account for the varying levels of linguistic development exhibited in the fossilized speech of the three second language learners studied here. Within the framework of second language learning these extra-linguistic factors take the form of social and psychological distance (Schumann 1975, 1976). Further examination of these two factors suggests that psychological distance exerts a greater effect on the second language learner's degree of acculturation than does social distance. In addition, the learner's motivational orientation seems to be the most influential aspect of psychological distance which determines the degree of acculturation toward the ‘model’ language group and consequently the degree of linguistic development toward the ‘model’ language.