Why do dogs chase their tails?
Well you see, realistically, they have self image issues which also accounts for their lack of appreciation for mirrors. Philosophically, it could of course be a question of ethics, but by nature, dogs are conspicuous in their absence of moral reason, or any other kind of reason. Therefore, we can assume they are idealists and everyone knows idealists are easy!
There you are. Any better ideas?
So glad we were able to help, Bardi the Boxer and Jona G.