So, What's a Weed?

What’s so wrong with weeds?  Here’s one old-timer’s opinion:

The New England Farmer
May 21, 1853
Vol. VIII, No. 21
WEEDS.
Weeds, it should be recollected, are always more exhausting to soil than either roots or grain crops.  They are indigenous, consequently gross feeders, and abstract from the soil only those elements of fertility which are essentially and indispensably requisite to sustain the more valuable and cultivated crops.  It should ever be a rule with the farmer, to allow no plant to perfect its seed on his premises, that will, in anyway, diminish the productiveness of his soil.

As you know, I have a lot of respect for the old timers' opinions.  But this time, this Heirloom Orchardist disagrees with the above writer, who was probably one of the editors of the New England Farmer.
First, we don’t really know whether the above writer's “weeds” are more exhausting to soil than root or grain crops.  That’s a pretty broad opinion, particularly since we don’t know which weed we’re talking about, and also because both root and grain crops themselves are pretty darn exhausting to soil.
Second, we know that (of course) not all weeds are indigenous.  And many of the worst weeds, the most invasive types, are aliens.
Third, maybe it’s not so bad to “allow plant(s) to perfect their seed(s).”  Maybe that’s part of the surprise of gardening….hmm…it all depends on what you consider to be a weed…

So, what’s a weed?  Well, here’s my definition…and I immodestly take complete credit for this definition, ‘cause I thought it up.  But I understand that it’s so darn obvious, that someone else much smarter than me, probably thought it up first:

A weed is any plant, growing in the wrong place.

This definition allows me multiple options on what to do with that weed…that plant…that thing growing in my garden that I know I didn’t put there.  Not all weeds need to be pulled up, and placed in the sun to desiccate.  I can transplant a weed!  I can leave it alone!  It’s up to me.  Here, take a look at my patch of Bleeding Heart (Dicentra spectabilis):

This early spring bloomer always cheers me up in May.  Sure, it disappears in mid summer, and might leave a void in the garden. But there are so many other things going on by that time, that I hardly notice.  Look closely at the ground in front of my Bleeding Hearts….what’s all that green fuzz?  Those are seedlings.  Weed seedlings?  Maybe, I didn’t plant them.  And they’re just the right size to get with my hoe.

But I’m not gonna get them with my hoe.  I’m gonna let them stay.  There’s a good chance these seedlings are little volunteer Bleeding Hearts .  We shall see.  If not, well then, I’ll declare them to be “gross feeders” taking from my soil “those elements of fertility which are essentially and indispensably requisite to sustain the more valuable and cultivated crops.”  And those more valuable and cultivated crops would not be weeds, of course, they’d be my Bleeding Hearts.