what is the difference between ...

a valid logical inference

and

a true fact statement?

I am pretty sure these two things are the same.

~

How many readers have ever failed while 
trying to solve a sudoku puzzle?

Here in America, they put them in the 
newspapers lately.  I don't remember that 
happening 20 years ago.  However, most
people know what a crossword puzzle is.


Follow a link to dictionary.com and lets 
find out what an invalid sylogism is.

I believe it is a false statement.