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Arithmetic and tautology

You have provided a single statement, "three plus four equals seven".

A tautology would be something like:
3+4=7, therefore 3+4=7.

The following two are tautologous :-

There are 7 days in a week
There are (3+4) days in a week.

Here's two tautologies :-

If you have (3+4) apples, then you also have 7 apples
If you have (3+4) bananas then you have (4+3) bananas.

Isn't a tautology saying the same thing in two different ways?

3+4=7, therefore 3+4=7 is an identity.

Surely a tautology is something obvious that someone might choose to deny, like 'Right-wingers are liars'. 5 + 2 = 7 is something even they wouldn't deny, so it is a (provisional) fact. A cliché is something that is too obvious to be worth stating:

My cat
does sit
upon a mat.
 
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The two sides are not equal logically.

They are only equal by definition.

4 = 4 is a logical equivalence however.

A thing is logically equivalent to itself. A meaningless tautology.

How do you apply these definitions without logic?

An example of an operation would be: When you get to the intersection turn left.

What logic is applied in turning left? It is just following an order.
 
How do you apply these definitions without logic?

An example of an operation would be: When you get to the intersection turn left.

What logic is applied in turning left? It is just following an order.
I still don't understand Juma's question.

That you need logic to apply definitions in arithmetics is part of arithmetic being a logical system. However, that doesn't make a statement like "3 + 4 = 7" a tautology since the proposition "3 + 4 = 7" is not always true. "3 + 4 = 7" is not necessarily true if you don't include all assumptions, and arithmetical definitions in particular, in your statement. Without those, 3 + 4 = 10 in base 7 for example and 11 in base 6.
EB
 
An example of an operation would be: When you get to the intersection turn left.

What logic is applied in turning left? It is just following an order.
I still don't understand Juma's question.

That you need logic to apply definitions in arithmetics is part of arithmetic being a logical system. However, that doesn't make a statement like "3 + 4 = 7" a tautology since the proposition "3 + 4 = 7" is not always true. "3 + 4 = 7" is not necessarily true if you don't include all assumptions, and arithmetical definitions in particular, in your statement. Without those, 3 + 4 = 10 in base 7 for example and 11 in base 6.
EB

I don't understand it either.

A mathematical operation is an order to do something.

It isn't logic.
 
An example of an operation would be: When you get to the intersection turn left.

What logic is applied in turning left? It is just following an order.
I still don't understand Juma's question.

That you need logic to apply definitions in arithmetics is part of arithmetic being a logical system. However, that doesn't make a statement like "3 + 4 = 7" a tautology since the proposition "3 + 4 = 7" is not always true. "3 + 4 = 7" is not necessarily true if you don't include all assumptions, and arithmetical definitions in particular, in your statement. Without those, 3 + 4 = 10 in base 7 for example and 11 in base 6.
EB

Obviously that is implicated since 7 is not represented that way in base 7.
Yeez. That the use of suitable definitions is implied is a nobrainer.
 
I still don't understand Juma's question.

That you need logic to apply definitions in arithmetics is part of arithmetic being a logical system. However, that doesn't make a statement like "3 + 4 = 7" a tautology since the proposition "3 + 4 = 7" is not always true. "3 + 4 = 7" is not necessarily true if you don't include all assumptions, and arithmetical definitions in particular, in your statement. Without those, 3 + 4 = 10 in base 7 for example and 11 in base 6.
EB

I don't understand it either.

A mathematical operation is an order to do something.

It isn't logic.

Yes it is, see Speakpidgeons answer.
 
I still don't understand Juma's question.

That you need logic to apply definitions in arithmetics is part of arithmetic being a logical system. However, that doesn't make a statement like "3 + 4 = 7" a tautology since the proposition "3 + 4 = 7" is not always true. "3 + 4 = 7" is not necessarily true if you don't include all assumptions, and arithmetical definitions in particular, in your statement. Without those, 3 + 4 = 10 in base 7 for example and 11 in base 6.
EB

Obviously that is implicated since 7 is not represented that way in base 7.
Yeez. That the use of suitable definitions is implied is a nobrainer.
You're confusing logic and linguistic practice.

The question was whether 3 + 4 = 7 is a tautology, not whether we see how it can be construed as being true.
EB
 
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