The line that is both logical and nonsensical is: “But if you HADN'T done them,” the Queen said, “that would have been better still; better, and better, and better!”
This statement is logical in that it suggests a scenario where not committing an act leads to a universally better outcome. However, it is nonsensical because it expands on the idea of “better” without a clear context, suggesting an infinite state of improvement that doesn't necessarily translate to reality.