In this paper, the application of fuzzy logic in mathematical education is viewed from the perspective of pre- school education. The aim of the paper is to give a brief overview of examples from the literature related to fuzzy logic and to point out the presence of fuzzy linguistic variables in the everyday life of a preschool child, as well as the importance of developing and respecting the approximate reasoning of preschool children. Although crisp mathematics requires crisp arguments that characterize our cognitive development, preschoolers start from common argumentation and use vague words. Fuzzy logic is an excellent tool for supporting such approximate reasoning which allows preschoolers to model real-life situations using vague words.