Why should we need to re-prove theorems that have been proved already?

[Mike_bb]

Hello!

If theorems always work and they are true statements then why should we need to re-prove theorems that have been proved already by many people?

Could anyone provide examples that confirm necessity of re-proving theorems?

Thanks!

 

[pasmith]

So that we understand the proofs, and can satisfy ourselves that they are indeed correct proofs. We don't take other people's word for it in mathematics.

 

[kuruman]

Also, so that we learn how to proceed in order to establish that something is correct. This is essential if the game is to acquire new knowledge and we want to be sure that it is correct and on the right track.

 

[PeroK]

Hello!

If theorems always work and they are true statements then why should we need to re-prove theorems that have been proved already by many people?

Could anyone provide examples that confirm necessity of re-proving theorems?

Thanks!

Because the ones that haven't been proved are either unknown or too difficult.

You could say the same about learning to program. Or, carrying out experiments in a physics or chemistry lab that have been done countless times before.