"Equality and identity" in Chapter 1 states that "constructing a new object that is the same as an existing one will give a result that is equal, but not identical, to the existing one". This is not quite true in the most general case (despite being a reasonable assumption for practical purposes).
We should find a more cautious formulation for that. One suggestion was to add "by default" to the sentence (although that's still not quite right because the default for int is different for example). Maybe "usually" or just "It is useful to think about it as this although it's a bit more subtle".