We experimentally and numerically delve into the life-like behavior of an oil droplet in an aqueous surfactant solution in response to changes in the volume and composition ratio of the droplet. Much research has been dedicated to investigating living and non-living systems independently, albeit the boundary between the two remains unclear. To address this issue, we conducted experimental observations and identified several types of spontaneous motion exhibited by the oil droplet, which varied depending on its parameters. We then quantified the characteristic motion patterns utilizing analysis from multiple aspects and compared the differences between oil droplets - as an example of non-living material -and Tetrahymena thermophila - as a living system. Furthermore, in an attempt to reveal the deterministic or stochastic rule governing each system, a numerical simulation of the Langevin equations was performed.

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