Pareidolias is a series of fluid animations presenting an indeterminate content. This work resulted from a study of the activity of the brain once faced with an indeterminate or unfamiliar forms. How to ensure the immersion of the perceiver by captivating his attention and by triggering deep cognitive activities related to mental imagery ? That was the challenge of the series. In order to generate these intriguing shapes, I had to engage, paradoxically, in a process of creation based on randomness. In my PhD research, I called this very process poetics of the indiscernible.