Yes, there is. Let's take an easy example:
Let A(x,y) be the statement
x + y = 0
Then ∀x ∃y: A(x,y) translates
"For every x, there is some y such that x + y = 0"
And of course, that's true; for any x, we just let y = -x.
But the statement ∃y ∀x: A(x,y) translates
"There is some y such that for EVERY x, x + y = 0"
and of course, that's not true. There is no number that can be added to ANY number to get 0 as a result.
I hope this helps clear up the distinction.
The qualifications apply left to right, so
∀x ∃y: A(x,y) means that for EVERY x, the statement ∃y: A(x,y) is true, but
∃y ∀x: A(x,y) means that for some y, the statement ∀x: A(x,y) is true.
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Verified answer
Yes, there is. Let's take an easy example:
Let A(x,y) be the statement
x + y = 0
Then ∀x ∃y: A(x,y) translates
"For every x, there is some y such that x + y = 0"
And of course, that's true; for any x, we just let y = -x.
But the statement ∃y ∀x: A(x,y) translates
"There is some y such that for EVERY x, x + y = 0"
and of course, that's not true. There is no number that can be added to ANY number to get 0 as a result.
I hope this helps clear up the distinction.
The qualifications apply left to right, so
∀x ∃y: A(x,y) means that for EVERY x, the statement ∃y: A(x,y) is true, but
∃y ∀x: A(x,y) means that for some y, the statement ∀x: A(x,y) is true.