Of course, the dealers who service such collectors look a lot. They scrutinize repeatedly works at auction in which they're interested, sometimes asking to view them in private, in darkened rooms under infra-red light, the better to determine condition. There's a lesson in that, no matter your price range: Just as you shouldn't buy a sound system you don't first hear, you shouldn't buy art you (or a trained, designated agent) don't first see - unmediated, in-person, one-to-one.

It has to be seen

Visual art has to be seen. And true collectors, as opposed to acquisitors and traders, derive pleasure from it because, beyond the social and financial promise of collecting, the firsthand experience of art gives something we cannot get any other way. Works of art are not only ideas. They're objects with nuances that can be perceived solely through direct encounter. Just as recordings do not capture the experience of live music, so do art objects' reproductions, electronic or otherwise, fail to convey the nuances in visual art that in most periods throughout history have determined desirability and real value.

Until buying art online becomes entirely buying art on approval - meaning the work itself, not a reproduction, is sent, viewed, purchased or sent back - I cannot recommend it for much beyond the most inexpensive decorative objects. Even then, however, you'll pay insurance, postage and handling to see what an art gallery displays for free, stands behind and frequently educates you about. That, I would think, outweighs shopping convenience.

So you're going to do it anyway? OK. I am here to suggest how the Internet can help beginners. First, grasp that digital reproductions merely have taken the place of unreliable slides and catalog illustrations. Drastically reduced in size and minimizing qualities of surface, they give a highly imperfect idea of a work's impact, conveying little detail and less about physical condition.

In my experience, discrepancies between artworks and their reproductions occasionally have been so great as to convince me I saw entirely different pieces.