It is known that the golden and silver ratios of about 1:1.5 give the human brains comfort. Then, there is also the symmetric ratio of 1:1 in ORIGAMI. The present report clarifies the reason why the human beings feel comfort in these ratios. Moreover, we find the aqua ratios for inducing well-being in the human brains, which also include the ratios around the golden and silver ones. Actual experimental data on the brains gives an evidence for the relation between feeling of comfort and brain structure.