This is a sentence which is not written in past tense.
This is a word which is not absurd.
This is a letter which is not any better.
But what is it?

The scientists thought about it for a long time, but they gave up in the end.
The evil people investigated it for evil purposes, but they gave up in the end.
"An object cannot both be a sentence, a word, and a letter at the same 
time!" everybody kept saying.
Then, one day, in came a quantum particle. It said "Hi", but it also 
said "Farewell". At the same time. Everybody was schocked.

But they were still not sure.

Then, another day, a fly appeared. While the peoples' uncertainty switch 
was still on, they were all determined on killing the fly. They were 
certain and uncertain at the same time.

"This is a coincidence!" a scientist said. So they were still not sure.

Then, on a third day, the second day showed up. It was followed by the 
first day. People were surprised, as the days officially lay in the 
past. But they realized that all three days suddenly existed on the same 
day. They did not understand this.

And so they ignored it.


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Based on a true story