Still better than Anthropic. If I create someday doomsday device, its turn off code will be to sort Anthropic models by strength given only their names, without access to the internet.

Before Mythos/Fable they were simply size-ordered. A Haiku is a small poem of 3 lines, a Sonnet has 14 lines and an Opus is a larger work.

I suppose a Fable is seen as larger. But some of them can be quite short, and not generally considered poetry.

I found Anthropic to be pretty intuitive.