The present study centers on the verbs of motion, which arc a particularly appropriate subset of lexicali/cd concepts to begin the exploration of how the human mind operates. The semantic field of verbs cf motion is briefly analyzed, and results of sorting tasks are reported to specify the organizing concepts of the field. Direction and causality are shown to be two of the most important, and are used to illustrate what is involved in semantic decomposition. In the second half, the paper focuses on the relation between perception and language by examining the perceptual hases of these semantic distinctions. Results of various rt experiments arc reviewed, from which it is concluded that there is no experimental support for the idea that the more complicated the semantic decomposition of a verb is. the longer it will take to use it or understand it This should lead psycholinguists to pay further attention to the problem of how to combine a structural description of the lexicon with a functional description of language comprehension.