How short can a poem be?

How short can a poem be before it’s just a few words on a piece of paper, before it’s not a poem? Then again, what is a poem?
There is a one-letter poem apparently, by the American poet and novelist, Aram Saroyan. It’s called, well, I can’t really type what it’s called. The poem consists of a letter m but with four legs, rather like the letters r and m run into one another.

How would you read it?
I have no idea and maybe that’s the point, it’s there to make you think.
I’m sure that there are many other short poems out there, it’s not an abyss I’ve gazed long into, just in case it gazes back. I only began looking for short poems as a sideline to my own short poem below.

I for my poetic sins like to allude to the unknown or unknowable and when it gets to the point that you have to think about it for too long, I think it rather misses the point.

I’m not saying that it’s wrong to write in unknown terms, it’s just not for me. I have to admit that when I started poking about on t’interweb and found that poem/letter/symbol by Aram Saroyan I kinda liked it.
“Why didn’t I think of that?” a part of my brain said.

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Reality Daze

Is it a short poem or a lost question,
that flows quickly from pen onto blank paper?

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Reality Daze is dated 20th January 1979 and I’ve no other versions of it nor does it occur anywhere as part of a longer piece, so I guess it did just flow from pen onto empty paper.

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