Charlie Finch, critic, Artnet
Caveat emptor.

Thigh Master, editor, culture blog Thighs Wide Shut
Why should it matter if the opinion comes from a stuffy journalist who addresses actors as Mr. and Ms. or from some slothy guy blogging the night away in his parents’ basement?

Adam Feldman
A critic should have a solid base knowledge of the field he or she is discussing. The other base qualifications are more slippery: intelligence, open-mindedness, sensitivity, taste, an ability to write well. As these don't always come bundled in the same package, it is up to the reader to decide whom he or she trusts most. In general, it helps to read and compare reviews of shows one has already seen, and see which critics a) seem to coincide most often with one's own taste in art (to feed one's existing sensibility), and b) have the most interesting things to say and the most compelling way of saying them (to help expand that sensibility).

Cara Joy David, theater blogger
The only prerequisite that has ever existed for critics is that they be hired. There were never any standard qualifications. How did anyone ever know who to trust? Did they trust whoever wrote for The New York Times? Was it ever that simple? Of course there are more choices now—a choice for every taste. You trust whose tastes agree with yours. I enjoyed Tom Stoppard's Rock 'n Roll more than his Coast of Utopia trilogy. I think the A Chorus Line revival is hopelessly mediocre. And I believe Martha Plimpton is a superb stage actress. So I try to find the critic who agrees with me on these points--and whatever other ones that randomly pop into my mind--and I know that, in the future, I can trust that person's opinion. 

David Fear, film critic, Time Out New York
Any and all critics should have a solid understanding of the history of their medium.… An ideal critic should also be a good sociologist and understand how the arts reflect and refract the times; for example, it’s hard to form a critical opinion past either a simple yea or nay of 1950s melodramas or the impact of the Beatles on popular culture without understanding what was going on around these things at the times. You go from seeing something in one dimension to three.

Steve Smith
A professional critic needs a deep familiarity and a passionate engagement with the subject that he or she discusses, period. That can take the form of an advanced degree in an arts speciality, but it can also result from a serious self-directed pursuit of knowledge and exposure. A careful reader can generally gauge for him or herself the level of genuine expertise that a particular critic or blogger brings to bear in his or her work; in blogging, mutual acclamation also plays a part. The recommendation of one or a few established, respected bloggers can go a very long way in welcoming another voice into the ongoing discussion. Voices we trust help to guide us to new voices that we learn to trust.

Mike Wolf
It's hard to quantify, but a sense of history is really crucial. Isclarity of thought a prerequisite? Then that too. Consumers should use thesame guides they've used for years when deciding things like which doctorto trust, which auto-repair person, which plumber: Who speaks to you?Who's consistent? Who's proved worthy of trust? Whose values and outlookmake sense to you?

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