lol that’s actually awesome. I think this is a clear case where the fine tuning/prompt wrapping is getting in the way of the underlying model!

  Each of Sally's brothers has 2 sisters. One of these sisters is Sally, but who is the other sister? Since Sally has only brothers and no other sisters are mentioned, we can conclude that the other sister for each brother is also Sally.

It’s clearly taught to do Chain of Reasoning out of the box, but typing it out tricked it because of the short, declarative sentences trying to establish something like “individual” facts. Poor Anthropic!