Full Idea
Suppose someone were to say: "Imagine this butterfly exactly as it is, but ugly instead of beautiful"?!
Gist of Idea
Consider: "Imagine this butterfly exactly as it is, but ugly instead of beautiful"
Source
Ludwig Wittgenstein (Philosophical Grammar [1932], §127), quoted by Robert Fogelin - Walking the Tightrope of Reason
Book Reference
Fogelin,Robert: 'Walking the Tightrope of Reason' [OUP 2004], p.152
A Reaction
This reminds us that the concept of supervenience was originally introduced in aesthetics. Beauty is supervenient on physical form. But "Imagine how someone else might look at this butterfly and think it was ugly".