A Question of Logic

[lilithu]

1. If not A, then not B.

2. If A then B.

Question: Are 1 and 2 essentially the same thing?

 

[YmirGF]

It depends how one looks at the problem, really, but after considering this for a nanosecond or three...

No. All it implies is that there is an inherent relationship between A and B, not that they are the same thing.

 

[Magic Man]

No, they are not. An example is "If a book is not written by me, it is not good" for #1. For #2, that would mean "If a book is written by me, it is good". According to the first one, a book written by others cannot be good, but that doesn't mean that all books written by me are necessarily good, which is what the second one says. The first one makes no judgement on the quality of my books, just the quality of others'. The second one makes a judgement on the quality of my books.

 

[Halcyon]

I don't think so either.

If we assign A and B to objects, say A = apple and B = banana.

Then we say "If A is not yellow, then B is not yellow", it does not hold true for B, which is yellow. And the same for #2 " If A is red, then B is red" it again doesn't hold true for B.

 

[Mr Spinkles]

I agree with YmirGF and mball1297. It is not the same thing. For another example...

1. If it is not Saturday, then it is not the weekend. (False)
2. If it is Saturday, then it is the weekend. (True)

 

[Smoke]

No.

If not an odd number, then not 7.
If an odd number, then 7.

If not 7, then not an odd number.
If 7, then an odd number.

 

[Yerda]

What are you getting at, lilithu?

 

[lilithu]

Thanks guys. You've restored my faith in people's reasoning abilities.

So let's take a look at the Fifth Amendment, shall we?

No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury, except in cases arising in the land or naval forces, or in the Militia, when in actual service in time of War or public danger; nor shall any person be subject for the same offense to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.

The part in bold, "nor be deprived of life, liberty, or property, without due process of the law.

I would translate that as: If not A, then not B. with A being "due process of law" and B being "deprived of life, liberty, or property."

Would you agree that this logically translates to: If not A, then not B?

And if so, based on what you argued above, would you agree that the Fifth Amendment does NOT say: If A then B?

That is, the Fifth Amendment does NOT say if there is due process of law then it logically follows that one can be deprived of life, liberty, or property.

 

[lilithu]

What are you getting at, lilithu?

Such a clever lad you are.

 

[Magic Man]

Thanks guys. You've restored my faith in people's reasoning abilities.

So let's take a look at the Fifth Amendment, shall we?

No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury, except in cases arising in the land or naval forces, or in the Militia, when in actual service in time of War or public danger; nor shall any person be subject for the same offense to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.

The part in bold, "nor be deprived of life, liberty, or property, without due process of the law.

I would translate that as: If not A, then not B. with A being "due process of law" and B being "deprived of life, liberty, or property."

Would you agree that this logically translates to: If not A, then not B?

And if so, based on what you argued above, would you agree that the Fifth Amendment does NOT say: If A then B?

That is, the Fifth Amendment does NOT say if there is due process of law then it logically follows that one can be deprived of life, liberty, or property.

I figured it had something to do with that. You're right, it doesn't say "If A then B", but it doesn't rule it out either. It says that your rights cannot be taken away without due process, but it (at least the part you quoted) doesn't say that your rights can't be taken away after due process.

It's not that "If not A then not B" and "If A then B" are mutually exclusive. They just aren't synonymous. They can still both be true together.

 

[lilithu]

I figured it had something to do with that. You're right, it doesn't say "If A then B", but it doesn't rule it out either. It says that your rights cannot be taken away without due process, but it (at least the part you quoted) doesn't say that your rights can't be taken away after due process.

It's not that "If not A then not B" and "If A then B" are mutually exclusive. They just aren't synonymous. They can still both be true together.

Thank you. I agree. It does not rule it out. It doesn't speak to the death penalty one way or the other.

 

[Aqualung]

1. if not A, then not B
2. B then A

those are logically equivalent.

 

[lilithu]

1. if not A, then not B
2. B then A

those are logically equivalent.

Yes, THOSE are.

 

[Poisonshady313]

Thank you. I agree. It does not rule it out. It doesn't speak to the fedeath penalty one way or the other.

Not directly, but it does suggest that the people who wrote the 5th amendment knew that the death penalty was the standard way of doing things. They knew that they were taking people's lives and liberties and property, and that when due process was not provided, they could not go about punishing people in the usual manner of punishing people... which is to deprive them of property, liberty, and in some instances, life.

You said that the 5th amendment doesn't speak to the death penalty... you're right. It speaks to due process.

Spoken by people who understood that the death penalty was standard operating procedure. If the people who wrote the bill of rights intended to prevent the death penalty... they would have written something addressing it.

They did not.

 

[lilithu]

Not directly, but it does suggest that the people who wrote the 5th amendment knew that the death penalty was the standard way of doing things. They knew that they were taking people's lives and liberties and property, and that when due process was not provided, they could not go about punishing people in the usual manner of punishing people... which is to deprive them of property, liberty, and in some instances, life.

You said that the 5th amendment doesn't speak to the death penalty... you're right. It speaks to due process.

Spoken by people who understood that the death penalty was standard operating procedure. If the people who wrote the bill of rights intended to prevent the death penalty... they would have written something addressing it.

They did not.

Once again, I agree. I am not trying to use the Fifth Amendment as an argument against the death penalty. I am merely pointing out that it does not work as a constitutional argument in favor of the death penalty. Claiming such is logically flawed.

Thank you for acknowledging that the Fifth Amendment speaks to due process.

 

[Aqualung]

Yes, THOSE are.

1. Not B implies not A.
2. B or not A

Those are logically equivalent

 

[Poisonshady313]

Once again, I agree. I am not trying to use the Fifth Amendment as an argument against the death penalty. I am merely pointing out that it does not work as a constitutional argument in favor of the death penalty. Claiming such is logically flawed.

Thank you for acknowledging that the Fifth Amendment speaks to due process.

Will you admit that there is no constitutional argument against the death penalty?

 

[lilithu]

Will you admit that there is no constitutional argument against the death penalty?

People have used the "no cruel and unusual punishment" argument. I personally agree but fully admit that it's not compelling as obviously not everyone considers it cruel. (It's certainly not unusual.)

I have stated, probably about a half a dozen times now, that the Constitution does not speak either way about the death penalty. The argument arose when someone in the other thread was trying to claim that the Fifth Amendment grants govt the right to kill. That is the only thing I'm disputing at this point. It's wrong.

 

[9-10ths_Penguin]

People have used the "no cruel and unusual punishment" argument. I personally agree but fully admit that it's not compelling as obviously not everyone considers it cruel. (It's certainly not unusual.)

It's not?

According to Amnesty International, capital punishment was only carried out in 24 countries last year. I'd say it's fairly unusual.

Edit: and it's getting more and more unusual as time goes on.

 

[lilithu]

It's not?

According to Amnesty International, capital punishment was only carried out in 24 countries last year. I'd say it's fairly unusual.

Edit: and it's getting more and more unusual as time goes on.

I believe that the phrase was referring to "unusual punishment" with respect to us.

At any rate, it's not a strong enough argument to make capital punishment unconstitutional. I think we need an amendment.