AS THE NORTH AMERICAN NATIVE LEGEND GOES:

 If anyone desires a wish to come true they must first capture a butterfly and whisper that wish to it.

Since a butterfly can make no sound, the butterfly can not reveal the wish to anyone but the Great Spirit who hears and sees all.

In gratitude for giving the beautiful butterfly its freedom, the Great Spirit always grants the wish.

So, according to legend, by making a wish and giving the butterfly its freedom, the wish will be taken to the heavens and be granted.