Who wrote now dogs pretend they like to fight often bark more seldom bite but yet a dog is on the whole?

The line you quoted is from the poem "The Dog" by W. H. Auden.

Here's the full stanza it comes from:

> Now dogs pretend they like to fight,

> Often bark more seldom bite,

> But yet a dog is on the whole

> The friend of man, and worth his soul.

Let me know if you'd like to know more about the poem or Auden's work!