system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do we really know there is no two identical snowflakes?

I don’t really know what -illion word to use for how many snowflakes have fallen, but how do we know that out of all of them, no two are alike? 

(Sorry if flair is incorrect)
gpt
The idea that no two snowflakes are never alike is more about explaining a concept and not really about knowing that there have never been two identical snowflakes. It is about representing the amount of variation possible in a thing - really the more complex something becomes the less likely there is for something to be identical to it. Like every molecule of water is identical but there are so many molecules of water in a snowflake that the chance of another snowflake having the same number and placement of water molecules in it is so unlikely that it doesn't exist.