[W:444:664] Logic 101: How To Properly Reason

gfm7175 · Sep 12, 2018

Re: Logic 101: How To Properly Reason

New Lesson!!!!!!

Today, we will explore the following argument...

No cat is a biped.
All kangaroos are bipeds.
Therefore, no cat is a kangaroo.

Is this an example of logically valid argumentation, or is this argument invalid?

soylentgreen · Sep 12, 2018

Re: Logic 101: How To Properly Reason

Angel said:
I didn't give you a definition of a hypothetical syllogism; I gave you a conditional statement and asked whether or not it has a truth-value. If I understand you, your answer should be No. Am I correct in guessing your answer?

My mistake, i thought you were referring to the hypothetical syllogism definition you had given and not the statement about me and you.

This is what you meant.

If soylentgreen is correct about the conditional argument, then Angel is incorrect about the conditional argument.

If we look at the argument for validity then yes it is assigned a t/f value.

If we are looking at the argument for soundness then no as the truth of the conclusion is still in question by you while the truth of the premise is in doubt by you.

While on the other hand in any argument with you i would always see the above argument as being true.

As i keep telling you a truth / false value is only good for validity not for soundness.

soylentgreen · Sep 12, 2018

Re: Logic 101: How To Properly Reason

Angel said:
Sorry, man. I seem to have overlooked these posts of yours.

Correct. The "if" supposes the truth of the statement it introduces.

The validity goes to the form; truth tables verify validity by showing that true premises do not lead to a false conclusion in the form in question.

We agree up to this point.

But that a hypothetical argument "can not be a sound argument" seems to make hypothetical argument nugatory.

No, you have me wrong there. I am not saying that a hypothetical argument "can not be a sound argument". I am being specific here and saying that your particular argument about god is not a sound argument.

soylentgreen · Sep 12, 2018

Re: Logic 101: How To Properly Reason

gfm7175 said:
New Lesson!!!!!!

Today, we will explore the following argument...

No cat is a biped.
All kangaroos are bipeds.
Therefore, no cat is a kangaroo.

Is this an example of logically valid argumentation, or is this argument invalid?

Why do i have the feeling that you also are confused with sound and valid arguments.

To answer your question is valid as well as sound.

Now you try this one.

All toasters are items made of gold.
All items made of gold are time-travel devices.
Therefore, all toasters are time-travel devices.

is this a valid or invalid argument? Is it sound?

gfm7175 · Sep 12, 2018

Re: Logic 101: How To Properly Reason

soylentgreen said:
...deleted unsubstantiated assertion...

soylentgreen said:
To answer your question is valid as well as sound.

Correct!

soylentgreen said:
Now you try this one.

Sounds like fun!!

soylentgreen said:
All toasters are items made of gold.
All items made of gold are time-travel devices.
Therefore, all toasters are time-travel devices.

is this a valid or invalid argument? Is it sound?

The logical form of your argument is as follows...
All A are B.
All B are C.
Therefore, All A are C.

You have made a logically valid argument. However, your argument is not a sound argument because the premises are false.

soylentgreen · Sep 12, 2018

Re: Logic 101: How To Properly Reason

gfm7175 said:
Correct!

Sounds like fun!!

The logical form of your argument is as follows...
All A are B.
All B are C.
Therefore, All A are C.

You have made a logically valid argument. However, your argument is not a sound argument because the premises are false.

Correct. So who were you referring your " new lesson " to. Or was it just a general statement for any?

gfm7175 · Sep 12, 2018

Re: Logic 101: How To Properly Reason

soylentgreen said:
Correct. So who were you referring your " new lesson " to. Or was it just a general statement for any?

It was a general statement for any... Discussion died down and I got bored.

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

soylentgreen said:
No, you have me wrong there. I am not saying that a hypothetical argument "can not be a sound argument". I am being specific here and saying that your particular argument about god is not a sound argument.

Oh so! said Mr Moto. And why not? Because you don't believe in God?

soylentgreen said:
...
If soylentgreen is correct about the conditional argument, then Angel is incorrect about the conditional argument.

If we look at the argument for validity then yes it is assigned a t/f value.

If we are looking at the argument for soundness then no as the truth of the conclusion is still in question by you while the truth of the premise is in doubt by you.

While on the other hand in any argument with you i would always see the above argument as being true.

As i keep telling you a truth / false value is only good for validity not for soundness.

Our intuitions are unaligned on this, it seems.

I see the statement "If soylentgreen is correct about the conditional argument, then Angel is incorrect about the conditional argument" as necessarily true.

How about our other example:

"If I live in Sacramento, then I live in California."

Is that a true statement?

Can you kindly offer a conditional statement of your own that you deem true?

Quag · Sep 13, 2018

Re: Logic 101: How To Properly Reason

cabse5 said:
Why would you think I'd identify you as atheist?

You aren't agnostic, either. What are you?

What is the problem with Angel's argument?

You quoted Angle then myself and started talking about atheists. The implication is that I am an atheist.
As to Angels argument
If God created life, then life is providential.
If life is providential, then life is sacred.__
Therefore, if God created life, then life is sacred.

Can be rewritten:

If God created life, then life is not providential.
If life is not providential, then life is not sacred.__
Therefore, if God created life, then life is not sacred.
Both arguments are equally valid neither is sound because the then cannot be proven to follow the if in either case.

cabse5 · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Quag said:
You <cabse5> quoted Angle then myself and started talking about atheists. The implication is that I am an atheist.
As to Angels argument
If God created life, then life is providential.
If life is providential, then life is sacred.__
Therefore, if God created life, then life is sacred.

Can be rewritten:

If God created life, then life is not providential.
If life is not providential, then life is not sacred.__
Therefore, if God created life, then life is not sacred.
Both arguments are equally valid neither is sound because the then cannot be proven to follow the if in either case.

Angel said:
Dismissal again?

Here's your homework:

If G, then B.
If B, then M.
Therefore, if G, then M.

Is this a valid argument?

Does Quag think cabse5 thinks Angel is an atheist, too? Does Quag suppose that is why Angel uses Angel as their user ID and why Angel constructed their validity argument using God as one of the arguments? Is Quag conflating the meaning of the philosophical terms validity argument and sound argument? NO. He's spot on with his post that was quoted (athough it seems to me he came upon this realization late in the thread).

gfm7175 · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Quag said:
You quoted Angle then myself and started talking about atheists. The implication is that I am an atheist.
As to Angels argument
If God created life, then life is providential.
If life is providential, then life is sacred.__
Therefore, if God created life, then life is sacred.

Can be rewritten:

If God created life, then life is not providential.
If life is not providential, then life is not sacred.__
Therefore, if God created life, then life is not sacred.
Both arguments are equally valid neither is sound because the then cannot be proven to follow the if in either case.

Angel's example is valid and true (his major and minor premises are true). Your example is valid and false (your minor premise is true, but your major premise is false).

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

When is a Conditional Statement False?

gfm7175 said:
Angel's example is valid and true (his major and minor premises are true). Your example is valid and false (your minor premise is true, but your major premise is false).

cabse5 said:
Does Quag think cabse5 thinks Angel is an atheist, too? Does Quag suppose that is why Angel uses Angel as their user ID and why Angel constructed their validity argument using God as one of the arguments? Is Quag conflating the meaning of the philosophical terms validity argument and sound argument? NO. He's spot on with his post that was quoted (athough it seems to me he came upon this realization late in the thread).

Quag said:
You quoted Angle then myself and started talking about atheists. The implication is that I am an atheist.
As to Angels argument
If God created life, then life is providential.
If life is providential, then life is sacred.__
Therefore, if God created life, then life is sacred.

Can be rewritten:

If God created life, then life is not providential.
If life is not providential, then life is not sacred.__
Therefore, if God created life, then life is not sacred.
Both arguments are equally valid neither is sound because the then cannot be proven to follow the if in either case.

soylentgreen said:
No, you have me wrong there. I am not saying that a hypothetical argument "can not be a sound argument". I am being specific here and saying that your particular argument about god is not a sound argument.

"A conditional statement is ALWAYS TRUE except in the one case where the hypothesis is affirmed and the consequence does not follow."

Thank you to cabse5 and gfm7175 for their support.

Quag, soylentgreen -- please take five minutes to view the video.

The conditional statement "If God created life, then life is providential" is true except in the case where God created life and life is not providential.

Namaste

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Follow up

"A statement 'If p, then q' is TRUE IN ALL CASES except in the case where p is true and q is false."

gfm7175 said:
Angel's example is valid and true (his major and minor premises are true). Your example is valid and false (your minor premise is true, but your major premise is false).

cabse5 said:
Does Quag think cabse5 thinks Angel is an atheist, too? Does Quag suppose that is why Angel uses Angel as their user ID and why Angel constructed their validity argument using God as one of the arguments? Is Quag conflating the meaning of the philosophical terms validity argument and sound argument? NO. He's spot on with his post that was quoted (athough it seems to me he came upon this realization late in the thread).

Quag said:
You quoted Angle then myself and started talking about atheists. The implication is that I am an atheist.
As to Angels argument
If God created life, then life is providential.
If life is providential, then life is sacred.__
Therefore, if God created life, then life is sacred.

Can be rewritten:

If God created life, then life is not providential.
If life is not providential, then life is not sacred.__
Therefore, if God created life, then life is not sacred.
Both arguments are equally valid neither is sound because the then cannot be proven to follow the if in either case.

Quag · Sep 13, 2018

Re: Logic 101: How To Properly Reason

cabse5 said:
Does Quag think cabse5 thinks Angel is an atheist, too? Does Quag suppose that is why Angel uses Angel as their user ID and why Angel constructed their validity argument using God as one of the arguments? Is Quag conflating the meaning of the philosophical terms validity argument and sound argument? NO. He's spot on with his post that was quoted (athough it seems to me he came upon this realization late in the thread).

WTF????
How does any of those questions stem from what I posted?
I am not conflating the meanings of validity and soundness Angel however is.

Quag · Sep 13, 2018

Re: Logic 101: How To Properly Reason

gfm7175 said:
Angel's example is valid and true (his major and minor premises are true). Your example is valid and false (your minor premise is true, but your major premise is false).

The premises are no more true than those in my argument Hence Angles continued fail

soylentgreen · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
Oh so! said Mr Moto. And why not? Because you don't believe in God?

?

No, i already answered this. Not specifically because i do not believe in a god but the critique i would use is in your very first sentence. Even if a god did create the universe it does not neccesserily follow that there is a divine warrant. It could be the deists are correct and that god simply created the universe and then shown no interest in any events following that.

Our intuitions are unaligned on this, it seems.

I see the statement "If soylentgreen is correct about the conditional argument, then Angel is incorrect about the conditional argument" as necessarily true.

How about our other example:

"If I live in Sacramento, then I live in California."

Is that a true statement?

Can you kindly offer a conditional statement of your own that you deem true

The problem here is not that the statement is true but that you think the form the argument takes is what decides the truth. A conditional statement can be valid with both the premise and the conclusion being actually true then it is valid as well as sound. An example of where an if/then argument is valid but not sound would be your god statement. If God created the universe, then the universe enjoys Divine Warrant. Neither i nor you can say categorically that either premise or conclusion is true so it is not s a sound argument. but if we consider the statement to be true. An "if "true not "really"true. Then we can see that the conclusion follows from the premise and so it is a valid argument.

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Quag said:
The premises are no more true than those in my argument Hence Angles continued fail

You mean that your premises are no more false, Quig. Still, the first is semantic nonsense based solely on agnostic contrarianism. God and Providence are synonymous. So you're in effect asserting "If God intervenes, then God does not intervene." You're supposing a contradiction: If P, then not-P.

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Quag said:
WTF????
How does any of those questions stem from what I posted?
I am not conflating the meanings of validity and soundness Angel however is.

cabse5 said:
Does Quag think cabse5 thinks Angel is an atheist, too? Does Quag suppose that is why Angel uses Angel as their user ID and why Angel constructed their validity argument using God as one of the arguments? Is Quag conflating the meaning of the philosophical terms validity argument and sound argument? NO. He's spot on with his post that was quoted (athough it seems to me he came upon this realization late in the thread).

gfm7175 said:
Angel's example is valid and true (his major and minor premises are true). Your example is valid and false (your minor premise is true, but your major premise is false).

soylentgreen said:
No, i already answered this. Not specifically because i do not believe in a god but the critique i would use is in your very first sentence. Even if a god did create the universe it does not neccesserily follow that there is a divine warrant. It could be the deists are correct and that god simply created the universe and then shown no interest in any events following that.

The problem here is not that the statement is true but that you think the form the argument takes is what decides the truth. A conditional statement can be valid with both the premise and the conclusion being actually true then it is valid as well as sound. An example of where an if/then argument is valid but not sound would be your god statement. If God created the universe, then the universe enjoys Divine Warrant. Neither i nor you can say categorically that either premise or conclusion is true so it is not s a sound argument. but if we consider the statement to be true. An "if "true not "really"true. Then we can see that the conclusion follows from the premise and so it is a valid argument.

The conditional statement If God created life, then life is providential

1. is TRUE if God created life and life is providential.

2. is FALSE if God created life and life is not providential.

3. is TRUE if God did not create life and life is providential.

4. is TRUE if God did not create life and life is not providential.

soylentgreen · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
When is a Conditional Statement False?

"A conditional statement is ALWAYS TRUE except in the one case where the hypothesis is affirmed and the consequence does not follow."

Thank you to cabse5 and gfm7175 for their support.

Quag, soylentgreen -- please take five minutes to view the video.

The conditional statement "If God created life, then life is providential" is true except in the case where God created life and life is not providential.

Namaste

It is an assumed truth that god created life, not an actual undeniable fact. it is assumed that god cares about the life it created or gave it any special providence, not an actual fact. You have a valid argument not a sound one.

Where the hypothesis is affirmed and the consequence does not follow." is an invalid argument.

Example
If the earth is round then the grass is green. Both are true but the hypothesis and consequence does not follow so it is an invalid argument.

soylentgreen · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
Follow up

"A statement 'If p, then q' is TRUE IN ALL CASES except in the case where p is true and q is false."

Sigh! Once again i repeat. You are showing a table that tells us only the validity of the statement not whether it is a sound argument.

soylentgreen · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
The conditional statement If God created life, then life is providential

1. is TRUE if God created life and life is providential.

2. is FALSE if God created life and life is not providential.

3. is TRUE if God did not create life and life is providential.

4. is TRUE if God did not create life and life is not providential.

And again, Sigh! Thank you for pointing out validity. Now try and point out soundness.

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

soylentgreen said:
And again, Sigh! Thank you for pointing out validity. Now try and point out soundness.

I've agreed with your points about hypothetical syllogisms and the use of truth-tables to test validity and determine soundness, but in the latest exchanges I've moved the question of truth out of and away from the syllogism and focused attention on the statements alone, the statements which were used as premises in the syllogism, but which can be considered apart from the syllogism in which they were used.

That is why I asked you about those free-standing conditional statements, and asked you to give an example of a free-standing conditional state that you consider true.

Then I posted two university videos, not about syllogistic argument, but about the truth value of free-standing conditional statements. These videos support my contention that free-standing conditionals have truth values apart from syllogistic context.

We've left soundness behind us, and agreeably so. We're now looking at conditional statements and their truth value.

soylentgreen · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
I've agreed with your points about hypothetical syllogisms and the use of truth-tables to test validity and determine soundness, but in the latest exchanges I've moved the question of truth out of and away from the syllogism and focused attention on the statements alone, the statements which were used as premises in the syllogism, but which can be considered apart from the syllogism in which they were used.

That is why I asked you about those free-standing conditional statements, and asked you to give an example of a free-standing conditional state that you consider true.

Then I posted two university videos, not about syllogistic argument, but about the truth value of free-standing conditional statements. These videos support my contention that free-standing conditionals have truth values apart from syllogistic context.

We've left soundness behind us, and agreeably so. We're now looking at conditional statements and their truth value.

But i have no problem with truth values. Any statement regardless of whether it is a premise or a conclusion can only hold one of two values, truth or false. But assigning it a value of true does not mean it is factually true only that it be considered an " if " true. And the reason for doing that is to see that if the statements are considered as true then does the hypothesis lead to the consequence. if it does then the argument is valid, if not then the argument is invalid. Your god argument is valid but it is not a sound argument. Your argument for where you live is valid and sound.

Angel · Sep 13, 2018

Re: Logic 101: How To Properly Reason

soylentgreen said:
But i have no problem with truth values. Any statement regardless of whether it is a premise or a conclusion can only hold one of two values, truth or false. But assigning it a value of true does not mean it is factually true only that it be considered an " if " true. And the reason for doing that is to see that if the statements are considered as true then does the hypothesis lead to the consequence. if it does then the argument is valid, if not then the argument is invalid. Your god argument is valid but it is not a sound argument. Your argument for where you live is valid and sound.

I think we're in agreement.

The statement "If I live in Sacramento, then I live in California" has a truth value in and of itself. No? It is true even though I live in NYC.

gfm7175 · Sep 13, 2018

Re: Logic 101: How To Properly Reason

Angel said:
You mean that your premises are no more false, Quig. Still, the first is semantic nonsense based solely on agnostic contrarianism. God and Providence are synonymous. So you're in effect asserting "If God intervenes, then God does not intervene." You're supposing a contradiction: If P, then not-P.

Quag said:
...

Quag, the bolded is what you are not comprehending.