I Does Rearranging Quantifiers Affect Looping in Nested Statements?

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Rearranging quantifiers in nested statements can affect readability but not the logical meaning in this specific case. The expressions provided for "Some student did not ask any faculty member a question" yield equivalent interpretations regardless of the order of quantifiers. However, placing all quantifiers at the front may complicate understanding due to the need to track multiple variables and their relationships. There are scenarios where rearranging quantifiers could lead to different outcomes, although no specific examples were provided in the discussion. Overall, while it may not change the logic here, clarity can be compromised by such rearrangements.
SamitC
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Hello,
Suppose a problem statement is :

In a school, suppose S(x) is “x is a student”, F(x) is “x is a faculty member” and A (x, y) is “x asked a question to y”. Domain is all the people associated with the school. Write the following using quantifiers:
"Some student did not ask any faculty member a question".

Answers are:

So, ∃x [S(x) ∧ ∀y {F(y) → ¬ A(x, y)}] OR ∃x [S(x) ∧ ¬∃y {F(y)A(x, y)}]

Instead, if we bring all the quantifiers at the front, will it cause any difference? Like:
xy [S(x) ∧ {F(y) → ¬ A(x, y)}] OR ∃x ¬∃y [S(x) ∧ {F(y)A(x, y)}]

In general, does it ever cause any change in looping if we bring all quantifiers at the front? Or is there any specific reason not to put all quantifiers at the front?

Thanks
 
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In this case it doesn't make a difference, but sometimes it can make the expressions harder to read because you have to remember all the variables and their quantifiers before they are actually used.

There could be expressions where it makes a difference, although I don't have an example right now.
 
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mfb said:
In this case it doesn't make a difference, but sometimes it can make the expressions harder to read because you have to remember all the variables and their quantifiers before they are actually used.

There could be expressions where it makes a difference, although I don't have an example right now.
Thank you.
 
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