A dog, a bird, and a scientist walk into a poem...
Trying to find current scientific research in line with Finch's Venn diagram poems, I came across the abstract of an article in the February issue of Cognition regarding how infants perceive labels. The study, done by researchers at Oxford University and the University of Texas, tested the responses of ten-month-old infants to cartoon drawings and spoken category labels. The different conditions included showing drawings without labels; showing drawings with two "correct" labels (labels that matched the drawing's category); showing drawings with random labels; and showing all drawings with just one label. Infants learned the two "correct" categories in instances both without labels and with the two correct labels. In instances with random labeling, no category formation happened at all.
Eighteen months seems to be the average age when babies start to talk, though it really varies. I have friends whose daughter could said "thank you" before she was a year old - and under the appropriate circumstances, no less. So at ten months, our brains are furiously chipping away at language and all the accompanying development, like recognizing categories.
I think Finch's Venn diagram poems encourage readers, among other things, to revisit that early process of categorization. Actual Venn diagrams deal with sets and subsets of categories. In Finch's poems, each word becomes a representation of both a concrete noun and a more abstract idea. Take "dogsnout" in the dry county poem. It's a very concrete noun, and yet incredibly abstract. There are Rottweilers, Great Danes, Poodles, Jack Russell terriers... the list goes on. With the abstract word in the poem, you get just an image of a doglike quality - a loyal friend, waiting with his snout pressed against the window pane.
This sort of thinking wanders into the "prototype theory" idea in linguistics, where "some members of a category are more central than others" (definition from the Wikipedia entry on Prototype Theory). The example I recall from linguistics courses is "bird." When asked to think of a bird, most people will report thinking of a robin, while almost no one reports thinking of a penguin. Somehow the robin has more "birdness" than the penguin and, thus, is more central a member in the bird category.
I'm not sure my point here, other than thinking it's worthwhile to bring to consciousness those thought processes of ours that usually remain unconsidered. While playing with categories in poetry can be beautiful and freeing, I imagine labels unconsciously applied in life limit us. And we don't even realize it.

