In the Darukkhandha Sutra, the Buddha once scooped up some soil with his fingernail and asked his disciples which was greater, the soil on his fingernail or that on the whole earth. His disciples answered that the soil on his fingernail was so small that it was incomparable to that on the earth. The Buddha then said that in the same sense only a few beings were able to secure human form whereas far too many beings retrogress into the hells, hungry ghosts and animals.
hell beings like earth's dusk.
ghosts like sand in the river.
animal like skin cells.
asura like snow.
human & heaven beings like dirt in nails.
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