Logic lessons for Jak and Marg

[Mayan Elephant]

You observe:
All you've done (Aquinas) is created a proof based on a personal definition. You've defined God as "all good" You've not proven true God is all good, let alone even proven a god exists who could be all good. So your premises have not been proven true. And your conclusion can not be relied upon.

Right. And Aquinas established nothing. Superb analysis -- that if the major premise is not established, the conclusion is invalid. And, your correct “(Aquinas’) conclusion can not be relied upon.”

The original statement I wrote was this:

If God is all good, then truth must lead to God, since all truth is good. God is all good, therefore, all truth must lead to God.

I later defended this statement to demonstrate that it was logical, it fits the definition of a valid deductive argument, here was the defense I gave:

If in God, all goodness resides (thus to say of an object "A" that it is good, means that it participates in God's goodness in some way) and truth is good, then truth necessarily leads to God, since in God all goodness resides. The goodness of truth itself is found by following true things. Thus, given these explainations, here is an argument:

1. In God all goodness resides
2. all truth is good and
3. Therefore, truth leads to God

This is a valid argument. I challenge Jak or Marg to show that it is not.

Perhaps you both are not familiar with the terms 'logic' and 'argument,' because I know not much has been proven here (i.e. that God exists, that He is all good, etc) the only thing it proves is that if you accept 1 and 2, you are forced to accept 3. Demonstrate to me how it would be possible to accept the truth of 1 and 2, and not 3.

Proof of anything else aside from the above analysis was never my intent. We wouldn't be able to say much about anything if all our listeners demand of every logical statement a proof backed by solid evidence of all fundemental principles (i.e. that God exists, that He is all good, etc.) But in many circumstances, God's existence need not be established, because for many believers this premise has already been established, whether be faith or reason, or both. If I were to claim "this sentence proves that truth leads to God!" I agree, I would have a problem on my hands (because it only proves if 1 and 2, then 3), but that was never my intent. Clearly, if you read the original sentence in context of the original post, my message is plain; those who believe in God and believe that He is all good, need not fear truth! To demand such rigorous proof for every logical statement is ridiculous, we would not be able to say anything logical at all. For example, if a professor were to say:

1. Given Darwin's theory of natural selection, it is clear that all of our human traits are present because they have been genetically selected, passed down, over time, as means to survival of our species in our natural world
2. Love is a human trait
3. Therefore, it is clear that love is present among humans because it has been selected as a means to survival of our species

Nothing wrong with the validity in this argument, it is the soundness of the argument that is debatable. And indeed, there is no way for me to demonstrate that if you had heard this at someone's lecture on evolution, you would not raise your hand and say "excuse me, but you can't make that claim! You haven't established that Darwin's theory of evolution is true! You haven't proven anything!" But why expect proof that God exists and He is good from a Christian, before the Christian can say anything logical based on these beliefs? Doesn't my scientists do the same, with his unproven belief in natural selection?

Of course the professor (in this example) hasn't proven the theory of natural selection! He knows that! He has demonstrated that if you accept premise 1 and 2, you are forced to accept the conclusion 3. If anyone reading this has an adequate education in deductive logic, I would appreciate other explainations to illustrate my point, these two don't seem to get it, maybe someone else can explain better than I. Thanks.

[_marg]

Hopefully JAK will respond to you, in the meantime to get started you write:

I later defended this statement to demonstrate that it was logical, it fits the definition of a valid deductive argument, here was the defense I gave:

1. In God all goodness resides
2. all truth is good and
3. Therefore, truth leads to God

Please define God, truth and goodness.

by the way just because premises are put into a valid deductive formal form does not make the premises and their conclusion logical. Validity is only about form not about making sense or being logical. Logic is about a search for what is true.

[Mayan Elephant]

by the way just because premises are put into a valid deductive formal form does not make the premises and their conclusion logical. Validity is only about form not about making sense or being logical. Logic is about a search for what is true.

Wrong. You just illustrated the point that you don't know what logic is. Your definition is your own, you misunderstand that logic is a science, with rules such as validity and soundness.

Here is Wikipedia's definition of logic:

Logic, from Classical Greek λόγος logos (the word), is the study of the principles and criteria of valid inference and demonstration.

As a formal science, logic investigates and classifies the structure of statements and arguments, both through the study of formal systems of inference and through the study of arguments in natural language. The scope of logic is therefore large, ranging from core topics such as the study of fallacies and paradoxes, to specialized analyses of reasoning using probability and to arguments involving causality. Logic is also commonly used today in argumentation theory. [1]

Traditionally, logic is studied as a branch of philosophy, one part of the classical trivium, which consisted of grammar, logic, and rhetoric. Since the mid-nineteenth century formal logic has been studied as the foundation of mathematics. In 1903 Bertrand Russell and Alfred North Whitehead established logic as the cornerstone of mathematics with the publication of Principia Mathematica. The development of formal logic and its implementation in computing machinery is the foundation of computer science.

Here is the URL: http://en.wikipedia.org/wiki/Logic

Logic is more of a science much like mathematics than it is "a search for what is true," you confuse one use of logic (searching for truth) with its definition (a science with rules, like validity, soundness, etc.). Your misunderstanding is clear to those who study logic.

[_Aquinas]

1. In God all goodness resides
2. all truth is good and
3. Therefore, truth leads to God

Please define God, truth and goodness.

No, I won't. I don't care if you don't believe premise 1 and 2, plenty of people do and they are whom this statement was meant to be heard by. However, you don't even need to have a definition of these terms to show validity/invalidity. It's like math;

1. All g is in G
2. All T is g
3. Therefore, all T leads to G

You can show two plus two equals four and not five, so if you believe my argument is invalid, demonstrate it. Show us your skills.

[_marg]

previously: by the way just because premises are put into a valid deductive formal form does not make the premises and their conclusion logical. Validity is only about form not about making sense or being logical. Logic is about a search for what is true.

Aquinas: Wrong. You just illustrated the point that you don't know what logic is. Your definition is your own, you misunderstand that logic is a science, with rules such as validity and soundness.

The ultimate goal of logic is to use correct reasoning to reach a best approximation to what is true.

Logic is not solely deductive reasoning, which appears to be your primary focus. Deductive reasoning does not reveal anything more than what is already in the premises. And if the premises are nonsense, the conclusion can not be relied upon to be true, even if the argument is valid. The whole point of deductive reasoning is to determine if a conclusion can be relied upon to be true. And truth can only be relied upon if the premises are themselves true.

You write: I later defended this statement to demonstrate that it was logical.

Aquinas if your premises are nonsense, if you can not define the words within your premise it is not logical

Please look up the word logical I won't post the def'n.

Now as far as your wikipedia quote, you are misreading, and actually misquoting:


You write:

Logic, from Classical Greek λόγος logos (the word), is the study of the principles and criteria of valid inference and demonstration.

What wiki actually says is: "Logic, from Classical Greek λόγος logos (the word), is the study of patterns found in reasoning. The task of the logician is to set down rules for distinguishing between valid and fallacious inference, between rational and flawed arguments."

Logic is not solely about deductive reasoning. It is also about inductive. And notice Aquinas the words "between rational and flawed arguments." If your premises are nonsense the whole argument is nonsense. It is your burden to demonstrate your premises aren't nonsense. It's your burden to define the words you use in your argument. It's not good enough to present a valid form deductive argument and think you are presenting something logical.


You quote from wiki:

As a formal science, logic investigates and classifies the structure of statements and arguments, both through the study of formal systems of inference and through the study of arguments in natural language. The scope of logic is therefore large, ranging from core topics such as the study of fallacies and paradoxes, to specialized analyses of reasoning using probability and to arguments involving causality. Logic is also commonly used today in argumentation theory. [1]

They are including inductive reasoning ..anything with probabilities is inductive and inductive is informal not formal reasoning. Formal reasoning is deductive, it's called formal because of the recognized forms of validity.

Traditionally, logic is studied as a branch of philosophy, one part of the classical trivium, which consisted of grammar, logic, and rhetoric. Since the mid-nineteenth century formal logic has been studied as the foundation of mathematics. In 1903 Bertrand Russell and Alfred North Whitehead established logic as the cornerstone of mathematics with the publication of Principia Mathematica. The development of formal logic and its implementation in computing machinery is the foundation of computer science.

Correct but logic is not limited to formal reasoning and in fact it is not very practical for most everyday problems and reasoning.. And putting premises and conclusion into valid form does not make the argument logical.


Aquinas: "Logic is more of a science much like mathematics than it is "a search for what is true," you confuse one use of logic (searching for truth) with its definition (a science with rules, like validity, soundness, etc.). Your misunderstanding is clear to those who study logic."

I don't think you've even taken a first year course in logic. If you had you'd appreciate what the goal of logic is and as well that it's much more than formal deductive logic.

[_Aquinas]

Now as far as your wikipedia quote, you are misreading, and actually misquoting:[/color]


You write:

Logic, from Classical Greek λόγος logos (the word), is the study of the principles and criteria of valid inference and demonstration.

misquoting? Look up the URL, I copied and pasted this directly from Wikipedia:

http://en.wikipedia.org/wiki/Logic

Logic, from Classical Greek λόγος logos (the word), is the study of the principles and criteria of valid inference and demonstration.

Sorry, it is what it says. While I agree truth is the ultimate goal of logic, it is not it's definition. Logic is misunderstood as only "a search for what is true," that is too broad a definition. You could also include religous and mystical experience/practice into that definition. I'm quite certain prayer is a method used to search for truth, but logic searches for truth in a specific way, unlike prayer. Deductive logic is what I employed, and while you argue with the soundness of the statement, it was undisputedly valid. You still haven't been able to show that my argument was invalid, and you still aren't addressing the fact that the original statement was not meant to be a proof, only a deduction from premises (which are widely accepted by those who believe in God) to a conclusion (which was that truth leads to God).

Your problem with the argument is that you do not want me to present that God exists and that He is good to be true things; but too bad, both are true, your lack of belief is insignificant to the truth of these principles. We all hear about beliefs we don't agree with, it's part of life, deal with it. Many happen to believe the truths that God exists and He is all good, whether by faith or reason or both, and it was to those who do believe that the logic of my statement was useful. Are we to call the beliefs knowledge? Yes if it by reason, and no if it is by faith, but regardless, if by reason or faith you believe God exists and He is all good, you believe true things. Truth doesn't depend on peoples belief in it. If you want to know that God exists, Thomas Aquinas has five proofs for this, I've already given you the reference...

What I think is comical is when you call premises (like God is all good) nonsensical, yet you have faith in much more absurd first principles, like this:

My justification being [God's existence hasn't been proven because] if it had the news would be so large as to hit the newspapers.

I don't have as much faith as you Marg, I couldn't trust the truth of newspapers that much, but you apparently can. 'All hail the mighty newspaper, source of all truth!'

[_guy sajer]

I later defended this statement to demonstrate that it was logical, it fits the definition of a valid deductive argument, here was the defense I gave:

If in God, all goodness resides (thus to say of an object "A" that it is good, means that it participates in God's goodness in some way) and truth is good, then truth necessarily leads to God, since in God all goodness resides. The goodness of truth itself is found by following true things. Thus, given these explainations, here is an argument:

1. In God all goodness resides
2. all truth is good and
3. Therefore, truth leads to God

This is a valid argument. I challenge Jak or Marg to show that it is not.

As I understand it, logic deals, in part, with internally consistent arguments, which requires the conclusions follow from the premises. If I understand you, what you are asserting is that the above argument is a valid logical argument because the conclusion follows from the premises.

If I understand Marg, what she is asserting, in part, is that an argument may be internally consistent but still illogical, because its premises are false.

I agree with Marg; I think your premises are flawed. Your argument assumes the existence of God, something which you have not demonstrated, and which I dispute. Even were I to concede the existence of God, I further dispute the premise that "in God all goodness resides." Further, I dispute the premise that all truth is good.

Given that I find all three of your principle premises wrong (one implied, two explicit), I find your conclusion wrong also.

Consequently, I find your logic, if that's what we want to call it, wholly unpersuasive.

In it's place, I would like to put forward the following argument conforming to Aquinas' definiton of logic:

If George W Bush is all good, then truth must lead to George W Bush, since all truth is good. George W Bush is all good, therefore, all truth must lead to George W Bush

This argument fits the the definition of a valid deductive argument, here's the defense I give:

If in George W Bush, all goodness resides (thus to say of an object "A" that it is good, means that it participates in George W Bush's goodness in some way) and truth is good, then truth necessarily leads to George W Bush, since in George W Bush all goodness resides. The goodness of truth itself is found by following true things. Thus, given these explainations, here is an argument:

1. In George W Bush all goodness resides
2. all truth is good and
3. Therefore, truth leads to George W Bush

I've followed Aquinas' logic exactly, having pasting in George W. Bush for God.

So I pose the question to the rest of you. Is this a logical argument? Do you agree? Why or why not?

What's the difference between this argument and the one put forward by Aquinas?

[_silentkid]

Great post, Guy. I see the same flaws in the premises as you. To me, the first premise, "in god all goodness resides", is absurd. The god of the old testament acts contrary to any definition of goodness I have read, unless god's definition of goodness entails commanding the killing of his own children, among other atrocities. Maybe I am misunderstanding the original premise or the definition of goodness.

P.S. The sad thing is, there are probably people out there that believe your George Bush premise parody.

[_guy sajer]

Great post, Guy. I see the same flaws in the premises as you. To me, the first premise, "in god all goodness resides", is absurd. The god of the old testament acts contrary to any definition of goodness I have read, unless god's definition of goodness entails commanding the killing of his own children, among other atrocities. Maybe I am misunderstanding the original premise or the definition of goodness.

P.S. The sad thing is, there are probably people out there that believe your George Bush premise parody.

Well, as pointed out to us in an earlier thread, that God killed all of humanity was justified given the prevailing social mores of Old Testament socieities, and God was bound by prevailing social mores, so genocide was, by defnition, "good."

[_silentkid]

Well, as pointed out to us in an earlier thread, that God killed all of humanity was justified given the prevailing social mores of Old Testament socieities, and God was bound by prevailing social mores, so genocide was, by defnition, "good."

It amazes me how religious types can rationalize any type of absurdity.