Starting from the concept of arbitrariness as postulated by Saussure, this article will examine how the concept of arbitrariness leads to the departure from the previous linguistic theories and to the rise of new thinking in linguistics. In contrast to the pre-Saussurean linguistics, the concept of arbitrariness argues that sign does not correspond to reality, and as a corollary, that the signifier has no natural connection with the signified. In addition, the concept of arbitrariness points out to the constraints in the process of signification. To illustrate, this article applies Saussure's linguistics to examine the mechanism of the name-changing campaign in Taiwan.