Since evolution has not been observed nor has it been repeated, it is still theory and should be treated as one possible theory of origins. (religion.blogs.cnn.com)
There is no way to determine whether a dog is eating grass simply because they like it other than ruling out all other possible theories. (caninejournal.com)
Sunder Katwala suggested three possible theories for AV's defeat: the «silly question» theory (the British people just aren't interested in electoral reform); the «Clegg factor» and «it was Yes wot lost it.» (leftfutures.org)