The "wave" concept is integral to Saussure's model of geographical linguistics—it describes the gradient manner in which dialects develop. Linguistic waves, according to Saussure, are influenced by two opposed forces: parochialism, which is the basic tendency of a population to preserve its language's traditions; and intercourse, in which communication between people of different areas necessitates the need for cross-language compromise and standardization. Intercourse can prevent dialectical fragmentation by suppressing linguistic innovations; it can also propagate innovations throughout an area encompassing different populations. Either way, the ultimate effect of intercourse is unification of languages. Saussure remarks that there is no barrier to intercourse where only gradual linguistic transitions occur.