Grammar confirmation

[KEN JPN]

A friend of mine, teaching English at a cram school, made the below fill-in-the-blank question:

a) Mr. Brown said, "Dogs bark like wolves."
b) Mr. Brown said that dogs ( bark ) like wolves.

To me, both Sentences (a) and (b) look alright.
However, he told me that another teacher said,
"Before grammar, what these sentences state is not logical because NOT ALL THE DOGS bark like wolves".

I think this is a nonsense pointing out, because the sentence says "dogs", not "the dogs" or "all the dogs in the world without any exceptions".

A plural noun without "the" indicates "general species allowing some exceptions", right?

Horses are useful animals.
Dogs are faithful animals.

These sentences are perfectly correct and natural, though there may be some unuseful horses and unfaithful dogs in this world.

I would like to confirm that Sentences (a) and (b) are all correct.

Thank you in advance.

 

[Barb_D]

The use of "Dogs" implies that it applies to general category of dogs, without intending any specific exceptions.
Of course sentences like that will have exceptions. Dogs have four legs. Except Fido, who was hit by a car, and now gets along fine on only three legs. Etc.

However, to take exception to the truth of the sentence completely ignores the grammar point about reported speech. I can say "The moon is made of green cheese" and you still would have to say "Barb said that the moon was made of green cheese" for the purpose of the exercise. It doesn't matter if I'm right or not!

 

[KEN JPN]

Thank you very much for your comment.
I think I have completely confirmed my understanding.

 

[Barb_D]

No, I don't think you have. The idea that "dogs bark like wolves" was definitely intended to mean "the entire species of dogs."