A quick test of intelligence

Don't cheat! Because if you did, the test would be no fun. I promise, there are no tricks to the test.
Read the sentence below and count the F's in that sentence. Count them ONLY ONCE. Do not go back and count them again.

FINISHED FILES ARE THE RE-
SULT OF YEARS OF SCIENTIF-
IC STUDY COMBINED WITH
THE EXPERIENCE OF YEARS.

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Answer:

There are six F's in the sentence.
A person of average intelligence finds three of them.
If you spotted four, you're above average.
If you got five, you can turn your nose at most anybody.
If you caught six, you are a genius.
There is no catch.
Many people forget the "OF"'s.
The human brain tends to see them as V's and not F's.
Pretty weird, huh?