I think in general I agree with you, positive conditions are indeed easier to read. In this case, I think I prefer to stick with the negative though because the `check` function early-outs when it finds a condition that indicates that the target is safe on more than on occasion.

If it's ok with you I'd like both the early-out conditions to return `Safe` and the final statement to return `Appears`. I will adjust the statement to use `unless` as per your recommendation :) Thanks!