Statement to predicate formula
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Let B(x) mean “x is a bird”,
let W(x) mean “x is a worm”,
let E(x, y) mean “x eats y”.
There is a statement "Only birds eat worms".
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
logic predicate-logic quantifiers
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up vote
0
down vote
favorite
Let B(x) mean “x is a bird”,
let W(x) mean “x is a worm”,
let E(x, y) mean “x eats y”.
There is a statement "Only birds eat worms".
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
logic predicate-logic quantifiers
2
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
Let B(x) mean “x is a bird”,
let W(x) mean “x is a worm”,
let E(x, y) mean “x eats y”.
There is a statement "Only birds eat worms".
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
logic predicate-logic quantifiers
Let B(x) mean “x is a bird”,
let W(x) mean “x is a worm”,
let E(x, y) mean “x eats y”.
There is a statement "Only birds eat worms".
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
logic predicate-logic quantifiers
logic predicate-logic quantifiers
asked Nov 22 at 19:46
Ruben
246
246
2
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50
add a comment |
2
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50
2
2
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50
add a comment |
1 Answer
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1
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If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
Anything will be a bird if it eats anything which is a worm.
Any eater of worms is a bird.
Only birds eat worms.
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
Anything will be a worm if it is eaten by anything which is a bird.
Only worms are eaten by birds.
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
accepted
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
Anything will be a bird if it eats anything which is a worm.
Any eater of worms is a bird.
Only birds eat worms.
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
Anything will be a worm if it is eaten by anything which is a bird.
Only worms are eaten by birds.
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
add a comment |
up vote
1
down vote
accepted
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
Anything will be a bird if it eats anything which is a worm.
Any eater of worms is a bird.
Only birds eat worms.
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
Anything will be a worm if it is eaten by anything which is a bird.
Only worms are eaten by birds.
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
add a comment |
up vote
1
down vote
accepted
up vote
1
down vote
accepted
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
Anything will be a bird if it eats anything which is a worm.
Any eater of worms is a bird.
Only birds eat worms.
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
Anything will be a worm if it is eaten by anything which is a bird.
Only worms are eaten by birds.
If we translate this statement to predicate formula it will become:
$∀x∀y(W(x) ∧ E(y, x) → B(y))$
Anything will be a bird if it eats anything which is a worm.
Any eater of worms is a bird.
Only birds eat worms.
I was wondering will it be the same as $∀x∀y(B(x) ∧ E(x, y) → W(y))$ ?
Anything will be a worm if it is eaten by anything which is a bird.
Only worms are eaten by birds.
answered Nov 22 at 23:17
community wiki
Graham Kemp
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
add a comment |
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
Yeah, this does make sense. I thought that if only birds eat worms then it is the same as only worms are eaten by birds. Thanks for clarifying, your answer helped a lot!
– Ruben
Nov 23 at 0:05
add a comment |
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2
No; the second one means "Only worms are eaten by birds".
– Mauro ALLEGRANZA
Nov 22 at 19:50