"Old Mr. Bunny had no opinion whatever of cats." What does it mean?

In "The Tale of Benjamin Bunny" Beatrix Potter writes "Old Mr. Bunny had no opinion whatever of cats." What does it mean?

The cat looked up and saw old Mr. Benjamin Bunny prancing along the top of the wall of the upper terrace.

He was smoking a pipe of rabbit-tobacco, and had a little switch in his hand.

He was looking for his son. Old Mr. Bunny had no opinion whatever of cats.

He took a tremendous jump off the top of the wall on to the top of the cat, and cuffed it off the basket, and kicked it into the green-house, scratching off a handful of fur.

The cat was too much surprised to scratch back.

Looking in Google books, many of the instances of "had no opinion whatever of" X mean that he literally didn't have any opinion of X. However, there are a few instances of this phrase meaning "did not think highly of X"¹. For instance, Google books gives (Blackwood's Edinburgh magazine, 1885)

Flies! The landlord had no opinion whatever of those puny hooks with little tufts of feather upon them, which Mr Howard called flies. He would like to show them something that was a fly indeed: a marvel of mechanism, wound up by clock-work and kept thus in motion for twenty minutes at a time. That was a fly, ...

It's clear from the context that the phrase "had no opinion whatever of" means "did not think highly of" here, and given the context, I believe its use in Benjamin Bunny means the same thing.

¹ I would have used "thought very little of", but in the context of the original phrase, it's too ambiguous.

The explicit meaning of the sentence is that Old Mr. Bunny did not have an opinion either good or bad or complex or nuanced about cats, that he just didn't think of cats at all. The intended meaning is that he wasn't scared of cats, differently than one might expect of any rabbit.