(Note: This post has been extensively edited as of 5:32 AM Eastern on 10 Sep.)
The question of the protection by copyright of what has been termed "intellectual property" has always been of some moment. But with the advent of the Digital Age, and most particularly with the explosive rise of the World Wide Web, the question has assumed new prominence on all fronts. A small, very small, front (very small because monetary matters are not involved) has to do with the recent widespread emergence (also explosive) of weblogs. That copyright law automatically protects all original textual content posted on a weblog is a given (copyright is automatically secured at the instant of the first setting down of the text in fixed form). Enforcing that protection, however, is another matter altogether, and requires proper registration of the material with the U.S. Copyright Office before any enforcement action can be initiated, and the overwhelming majority of webloggers are not likely to take such a step to protect their writings within the blogosphere (protection of their writings outside the blogosphere is another matter; one not addressed here) for the very good reason that there's vanishing little reason to do so (because matters monetary aren't involved). Instead, webloggers depend not on copyright law to protect their intellectual property (i.e., their writings), but on a tacit "gentleman's agreement" of sorts with other webloggers.
One tenet of that tacit agreement decrees that a weblogger does not copy and paste another weblogger's post and publish it on his own weblog as his own. Another decrees that a weblogger does not post on his weblog another weblogger's text or portion thereof without proper attribution, usually in the form of a link to the original weblogger's post. These tenets are clear-cut and only rarely breached, and so present no problem.
And then there's the considerably more fuzzy area of the partial quote.
In the non-weblog world there's a precedent-rich legal doctrine known as Fair Use. It's a complicated area of copyright law (what area of copyright law isn't?), but essentially what it says is that for purposes of, say, a news story, critical review, comment, etc., a small portion of the copyrighted material may be used without infringing copyright. The absolute size or content of that small portion is nowhere set down, and would differ for different materials, and is therefore ultimately a matter for the courts to decide on a case-by-case basis.
Where the weblogger's tacit gentleman's agreement is concerned, however, there is, of course, no articulated doctrine of fair use, but it's implicit nevertheless, and there seems to be no general consensus on just how much of another weblogger's text may be quoted and still be deemed fair use. Clearly, quoting almost the entire text of another weblogger's post is not fair use in any circumstance, even properly credited as I just today had occasion to note on seeing with some dismay one of my own posts quoted almost in its entirety on another weblog (credited but not linked, even though my weblog itself was linked). Just as clearly, quoting the entire text of the central argument of another weblogger's post is also not fair use (as opposed to merely quoting enough to make clear the central argument itself), again, even when properly credited.
What to do, then? For what it's worth, here's my rule-of-thumb for determining fair use quote of another weblogger's post. Consistent with not misrepresenting what the original weblogger wrote in toto, I quote only enough to provide my following comments, critical or otherwise, their raison d'ĂȘtre or jumping-off place, and just enough to whet my readers' appetite for the reading of the original weblogger's entire post, which, except in those cases of my withholding for charitable or protective reasons the identity of the original weblogger, is always linked.
There's also a more subtle reason for my handling weblog quotes in that way: I assume that, like myself, the original weblogger wants what he's written to be read in the context of his own weblog. Form shapes and modulates substance (content) in subtle but meaningful ways, and a weblog's design, and even the layout of the text itself, can say worlds to a reader even when the reader is not himself consciously aware of exactly what's being said in that way, or even that anything is being said at all. And, no, there is no such thing as a "neutral" or non-influencing form; not even the form of an RSS feed, which is why on the RSS feed of my posts I permit only the first 100 words of each post to be published, thereby forcing readers to go to my weblog in order to read the entire post. (It's beyond my understanding why some webloggers provide the full texts of their posts for their RSS feed unless, that is, they're ashamed of their weblog's design, and would prefer folks not visit there at all.)
So there it is. My idea of fair use within the blogosphere. I welcome comments by other webloggers (I've enabled the TypePad Comments function for that purpose for this post alone).
Update 19 Sep: Comments are now closed.

It's The Music, Stupid!
Peggy

Without a link to the b log which prmpts this "gripe" this post is too abstract to be of much use as a starting point for discussion. But nice try
Posted by: David Sucher | 10 September 2004 at 09:22 AM
It isn't clear to me whether your fair use rule of thumb would sanction the reprinting in a blog (with attribution) of a short excerpt from another blog without any added commentary. I'm thinking of excerpts that speak for themselves and need no further commentary.
InstaPundit is filled with these short snippets. Terry Teachout's "Almanac" feature also does this, although he usually quotes from books, not blogs.
Reprinting a small excerpt seems more likely to whet the reader's appetite for the entire post than a simple "read this, it's great" reference. Something about blogging encourages this kind of back and forth linking, both as a way of expressing admiration (or contempt, I suppose) for a post and as a way to publicize a blog you particularly like (or, perhaps, don't like).
For instance, assuming you wrote this post after seeing that another blogger had reprinted one of your recent architectural posts, would you have considered it fair use if the blogger instead just reprinted (with attribution) the Wright retort about leaving art out in rain and left it at that?
Posted by: Outer Life | 10 September 2004 at 11:56 AM
David Sucher wrote: "Without a link to the blog which prmpts this 'gripe' this post is too abstract to be of much use as a starting point for discussion. But nice try."
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If all you got out of the post was that it was a "gripe," then you need to go back and reread it -- more carefully this time.
As for the "abstract" business, what's too abstract for some minds is concrete enough for others to comprehend the principle involved. And the principle is what the post is about, and not a personal matter.
ACD
Posted by: A.C. Douglas | 10 September 2004 at 03:39 PM
Outer Life wrote: "It isn't clear to me whether your fair use rule of thumb would sanction the reprinting in a blog (with attribution) of a short excerpt from another blog without any added commentary. I'm thinking of excerpts that speak for themselves and need no further commentary."
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Oh, sure. As long as the attribution provides a link to the original post. The problematic part of it is in determining the fair use size of the "short excerpt." Instapundit (whom I've not read in over a year now), to use your example, often quotes so much of the original post text that one feels it unnecessary to read the original post even though the link is there. Ditto Teachout. That's clearly NOT fair use.
And I guess that gives you the answer to your final question as well.
ACD
Posted by: A.C. Douglas | 10 September 2004 at 03:40 PM
No, AC, without seeing what upset you, it's difficult to make sense of your post.
Posted by: David Sucher | 11 September 2004 at 11:09 AM