Answer:
When set loose I fly away. Never so cursed as when I go astray.
If you break me, I do not stop working. If you touch me, I may be snared. If you lose me, nothing will matter.
I don't have eyes, but once I did see. Once I had thoughts, but now I'm white and empty.
Though desert men once called me God, today men call me mad. For I wag my tail when I am angry. And growl when I am glad.
What can be heard and caught but never seen?
When is it bad luck to see a black cat?