The fantastic light of firefly, which keeps fascinating the heart of Japanese from ancient time, and the ecosystem, are taken up as one of cure fields being benefit from the nature. In this study, from the viewpoints of semantic differentials and engineering, we focused on the light of firefly, and we examined whether they cause the human spirit any effects or not. It was possible to find for welfare utilizations that there is the high possibility that a sufficient cure effect exists in the light emission pattern of firefly and the ecosystem. This research is the first basic trial turned to the creation of cure space for hospices and welfare facilities, which utilize the firefly and the mini ecosystem artificially modeled in an enclosure.
