What's a Critic's Job? - Let's Check the Manual

Lots of talk about a critic's job around the web lately. It's always a good idea to revisit Alexander Pope's Essay on Criticism. Here is just a stanza:

Some ne'er advance a Judgment of their own,
But catch the spreading Notion of the Town;
They reason and conclude by Precedent,
And own stale Nonsense which they ne'er invent.
Some judge of Authors' Names, not Works, and then
Nor praise nor blame the Writings, but the Men.
Of all this Servile Herd the worst is He
That in proud Dulness joins with Quality,
A constant Critick at the Great-man's Board,
To fetch and carry Nonsense for my Lord.

I assign it in the cultural journalism class I teach.