Logically, What Is Logic?

[Pound_Coolish]

We use logic in everything we do, yet I recently came to the realization I’m not entirely certain what logic is.
According to some people I know, logic is the human mind using principles, inferences, et cetera to reason and discover reality.

I think though…

Suppose we were to debate about the nature of Heaven. I propose that Heaven is a field of daisies where we sit around in lederhosen eating chocolate bars and listening to Selena Gomez all day. You assert that Jesus said Heaven is a place of holy joy where we worship God forever, and that Jesus must be telling the truth because He is God, which we know because no one but either a madman, or a the most deceitful liar in history, or one who is God would make such claim, and Jesus was clearly not mad, nor a deceitful liar, therefore He must be God and what He says must be true. (I here reluctantly admit that maybe you’re right but we could listen to Selena as we worship.)

What did we just do?

We used logic. You used proofs of a fact to assert the fact. That is the human part of logic. Two people utilizing inferences and principles already in our universe to discover a truth already real.

Did you invent what you said?

If you had, it would be untrue. As it is true, it is not your invention. As it is true, it is logical.

… So, that is my opinion. However, it may easily be wrong, I simply can’t see where. The aforementioned acquaintances, however, seem to simply think I’m nuts basically. Thoughts?

Is logic inherently part of our universe or only the system people us to discover it?

 

[PietroPaolo]

Logic is just the formal “rules” of how we naturally think. It’s making explicit what we all do implicitly. It can’t be avoided. Even if someone said, “logic is just an invention of dead white men, so I don’t have to accept your logically proven point” they’d still be using logic to refute logic which is immediately ridiculous!

I highly recommend “Socratic Logic” by Peter Kreeft if you’re interested in logic.

 

[Pound_Coolish]

Thank you for the book recommendation, Kreeft is the best Catholic authority on logic I know of, so I shall look into that.

So then, according to you, logic is a human insitution? It is not something inherent in the universe? As Kreeft put it, incidentally, do we debate to see “… who is right or what is right?”

 

[PietroPaolo]

No, I’m not saying it’s a human institution. I’m simply saying it’s unavoidable for humans to think logically. Even arguments against logic have to be logical like those that claim logic is only an invention of the Greeks, therefore we can disregard it. Logic is just moving correctly from premises to conclusions. I wouldn’t say it is “something” in the universe as if a scientist could put “logic” under his microscope, but that isn’t saying it is a human invention - more of a human discovery.

 

[Pound_Coolish]

Ah. Thank you, very well explained, sorry for the misunderstanding. And, as I said, I shall be sure and get the book.

 

[Bob_Crowley]

We use logic in everything we do, yet I recently came to the realization I’m not entirely certain what logic is.
According to some people I know, logic is the human mind using principles, inferences, et cetera to reason and discover reality.

I think though…

Suppose we were to debate about the nature of Heaven. I propose that Heaven is a field of daisies where we sit around in lederhosen eating chocolate bars and listening to Selena Gomez all day. You assert that Jesus said Heaven is a place of holy joy where we worship God forever, and that Jesus must be telling the truth because He is God, which we know because no one but either a madman, or a the most deceitful liar in history, or one who is God would make such claim, and Jesus was clearly not mad, nor a deceitful liar, therefore He must be God and what He says must be true. (I here reluctantly admit that maybe you’re right but we could listen to Selena as we worship.)

What did we just do?

We used logic. You used proofs of a fact to assert the fact. That is the human part of logic. Two people utilizing inferences and principles already in our universe to discover a truth already real.

Did you invent what you said?

If you had, it would be untrue. As it is true, it is not your invention. As it is true, it is logical.

… So, that is my opinion. However, it may easily be wrong, I simply can’t see where. The aforementioned acquaintances, however, seem to simply think I’m nuts basically. Thoughts?

Is logic inherently part of our universe or only the system people us to discover it?

What we call “logic” is often a memory exercise, although it might be based on logical principles.

If I spend $2.85 at the supermarket, and I give the cashier a $5.00 note, I expect $2.15 change in return, based on the logic of mathematics.

But in fact my calculation is actually based on my old school tables which I learnt off by heart. I get the total by recalling the subtraction rules I learnt in school. I don’t actually sit down with the cashier and count out 500 one cent pieces, and then give him 285 of them, and count out the remaining 215 just to “prove” the logic.

I’m relying on memory, not “logic”. And that’s the case for a lot of what we do.

 

[seagal]

As it is true, it is logical.

… So, that is my opinion. However, it may easily be wrong, I simply can’t see where. The aforementioned acquaintances, however, seem to simply think I’m nuts basically. Thoughts?

Is logic inherently part of our universe or only the system people us to discover it?

Is logic part of our universe? The universe operates by following certain laws and principles but that’s not logic. The law of gravity determines that the apple will fall downwards from the tree, but the apple didn’t think “gravity exists therefore I must fall down”. Rather a humans observed that dropped objects always fall downwards, therefore there must be a force working on these objects. Logic doesn’t make things happen, logic simply a means of processing information in order to come to a conclusion. However, using logic doesn’t always lead to truth. Man observed the sun rising and setting for millennia and used logic to determine that the earth revolves around the sun. As we now know, this is not the truth. Scientists can observe the same data and come to different conclusions, using their powers of logic. When enough of them come to the same conclusion we call it the truth. This also applies to mathematics, philosophy, history, geography, and other fields of study.

 

[Charlemagne_III]

Is logic inherently part of our universe or only the system people us to discover it?

I think we live in a universe constructed upon logical principles derived from the mind of God. As Einstein said, he wanted to know God’s thoughts.

If the universe were not logical, our minds would be unable to perceive the laws of nature. Our minds would be in a continuing state of flux and chaos. We would not be able to find truth because there would be no truth to find. We would not be able to correct our errors because, there being no external logical structure, there would be no errors to correct.

Error itself is not the absence of logic. It is the misuse of logic. When we are sane, we all try to think with logic all the time. Sometimes we fail. If we are insane, we still think with deranged logic.

Thinking is not synonymous with feeling. Feeling is not so much irrational as supra-rational, a distinction Maritain liked to make often. Religion is holistic; it can be experienced both by our thinking process and our feeling process. Those who deny religion have cut themselves off from the power not just to think about God, but to *feel *the presence of God in their lives. That is a deliberate act. It is also a logical error, since there is no logical proof that God does not exist. In the absence of such logical proof, one must rely on one’s feeling. If one does not feel the presence of God, there must be a reason for shutting oneself off from God. There may be a thousand such reasons. I believe the principle reason, the reason that governs directly or indirectly all the other reasons, is the refusal to acknowledge the existence of an Ego bigger than our own.

 

[polytropos]

Is logic part of our universe?

I would not say that logic is part of our universe, but that the universe behaves logically. In other words, the universe is by nature intelligible. (Perhaps I would say that Being is intelligible by its nature.) The “laws of logic” are what we have abstracted from the universe and use as our standards of dialectic and reasoning.

Logic is also not exactly monolithic. There are various axioms of modal logic. There is debate over how “possible worlds” should be interpreted. There does not exist an airtight way of evaluating counterfactuals. Et cetera.