Mixing
Fitch Proof Exercise 13.8
Clash Royale CLAN TAG#URR8PPP
up vote
2
down vote
favorite
I am having trouble solving this Fitch Proof. Here is how far I’ve gotten
Only the last step is not checked out in Fitch but I think the logic works well.
Any help is appreciated.
Thank you
logic philosophy
asked Jul 20 at 17:38
Holly Feng
234
 |Â
show 3 more comments
up vote
2
down vote
favorite
I am having trouble solving this Fitch Proof. Here is how far I’ve gotten
Only the last step is not checked out in Fitch but I think the logic works well.
Any help is appreciated.
Thank you
logic philosophy
asked Jul 20 at 17:38
Holly Feng
234
Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51
 |Â
show 3 more comments
up vote
2
down vote
favorite
up vote
2
down vote
favorite
I am having trouble solving this Fitch Proof. Here is how far I’ve gotten
Only the last step is not checked out in Fitch but I think the logic works well.
Any help is appreciated.
Thank you
logic philosophy
asked Jul 20 at 17:38
Holly Feng
234
I am having trouble solving this Fitch Proof. Here is how far I’ve gotten
Only the last step is not checked out in Fitch but I think the logic works well.
Any help is appreciated.
Thank you
logic philosophy
asked Jul 20 at 17:38
Holly Feng
234
edited Jul 20 at 23:09
asked Jul 20 at 17:38
Holly Feng
234
asked Jul 20 at 17:38
Holly Feng
234
asked Jul 20 at 17:38
Holly Feng
234
234
Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51
 |Â
show 3 more comments
Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51
Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51
 |Â
show 3 more comments
1 Answer
1
active
oldest
votes
up vote
1
down vote
accepted
$$beginarray rl
& forall x .(Cx to forall y. (Dy to Fxy)) \
& quad boxedb \
& quad quad boxedc \
& quad quad quad Cb land Dc \
& quad quad quad vdots \
& quad quad quad Fbc \
& quad quad (Cb land Dc) to Fbc \
& quad forall y .(Cb land Dy) to Fby \
& forall x .forall y. (Cx land Dy) to Fxy \
endarray$$
Organizing your proof like this may work. Unfortunately the software is closed so it can't be openly verified.
answered Jul 20 at 22:33
DanielV
17.4k42651
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
add a comment |Â
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
accepted
$$beginarray rl
& forall x .(Cx to forall y. (Dy to Fxy)) \
& quad boxedb \
& quad quad boxedc \
& quad quad quad Cb land Dc \
& quad quad quad vdots \
& quad quad quad Fbc \
& quad quad (Cb land Dc) to Fbc \
& quad forall y .(Cb land Dy) to Fby \
& forall x .forall y. (Cx land Dy) to Fxy \
endarray$$
Organizing your proof like this may work. Unfortunately the software is closed so it can't be openly verified.
answered Jul 20 at 22:33
DanielV
17.4k42651
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
add a comment |Â
up vote
1
down vote
accepted
$$beginarray rl
& forall x .(Cx to forall y. (Dy to Fxy)) \
& quad boxedb \
& quad quad boxedc \
& quad quad quad Cb land Dc \
& quad quad quad vdots \
& quad quad quad Fbc \
& quad quad (Cb land Dc) to Fbc \
& quad forall y .(Cb land Dy) to Fby \
& forall x .forall y. (Cx land Dy) to Fxy \
endarray$$
Organizing your proof like this may work. Unfortunately the software is closed so it can't be openly verified.
answered Jul 20 at 22:33
DanielV
17.4k42651
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
add a comment |Â
up vote
1
down vote
accepted
up vote
1
down vote
accepted
$$beginarray rl
& forall x .(Cx to forall y. (Dy to Fxy)) \
& quad boxedb \
& quad quad boxedc \
& quad quad quad Cb land Dc \
& quad quad quad vdots \
& quad quad quad Fbc \
& quad quad (Cb land Dc) to Fbc \
& quad forall y .(Cb land Dy) to Fby \
& forall x .forall y. (Cx land Dy) to Fxy \
endarray$$
Organizing your proof like this may work. Unfortunately the software is closed so it can't be openly verified.
answered Jul 20 at 22:33
DanielV
17.4k42651
$$beginarray rl
& forall x .(Cx to forall y. (Dy to Fxy)) \
& quad boxedb \
& quad quad boxedc \
& quad quad quad Cb land Dc \
& quad quad quad vdots \
& quad quad quad Fbc \
& quad quad (Cb land Dc) to Fbc \
& quad forall y .(Cb land Dy) to Fby \
& forall x .forall y. (Cx land Dy) to Fxy \
endarray$$
Organizing your proof like this may work. Unfortunately the software is closed so it can't be openly verified.
answered Jul 20 at 22:33
DanielV
17.4k42651
answered Jul 20 at 22:33
DanielV
17.4k42651
answered Jul 20 at 22:33
DanielV
17.4k42651
answered Jul 20 at 22:33
DanielV
17.4k42651
17.4k42651
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
add a comment |Â
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
Thank you so much for helping! I've figured it out
– Holly Feng
Jul 20 at 23:18
add a comment |Â
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Here's a MathJax tutorial :)
– Shaun
Jul 20 at 17:41
You should delete step 7. You already made the assumption in step 2.
– DanielV
Jul 20 at 17:42
@DanielV: Except that it's the assumption in a sub-proof. That's how you set up a $forall$ Intro.
– Adrian Keister
Jul 20 at 17:58
Step 10 looks right to me. Only thing I can think of is that in 2, you're assuming the $textCube(b)land textDodec(c),$ involving $c,$ whereas in line 11, the rest of your expression involves $y$ instead of $c$.
– Adrian Keister
Jul 20 at 18:03
Step 7 is the assumption in a sub-proof. Without it i have no idea how to eliminate the ∀ in 6 and get the FrontOf(b, c)
– Holly Feng
Jul 20 at 18:51