The word 简单 is formed through the combination of two independent characters, each contributing a layer of meaning that merges into a single abstract concept. The first character, 简, originally depicted bamboo slips used for ancient writing, carrying connotations of something straightforward, brief, or unadorned. The second, 单, means single, alone, or uncomplicated. When paired, their individual notions of "unadorned" and "single/unmixed" semantically reinforce one another to conceptually create the modern meaning of "simple" or "easy", representing a fusion where both components contribute directly to the resultant idea.