Descriptive analysis of foods involves the communication of sensory concepts which are defined using standard stimuli. The concept created by a single NaCl standard stimulus was measured as a set of probabilities. It was found not to be the same for each judge. Disagreement between judges can thus be caused by variations in conceptualization, as well as sensation. This has important implications for the definition of terms in descriptive analysis. The concept was found not to generalize to strong monosodium glutamate (MSG) stimuli which raises questions about reports that MSG tastes salty at high concentrations. Effects on the concept of context, time and variation of standards were also noted.