I’ve posted before about one way that writing poetry can make you smarter (although I should have said “wiser”); here is another:
Sometimes when people first begin to attempt to write poetry, they complain about the metrical rules (or “constraints”) of formal meter, and they may even abandon formal meter in favor of free verse, which allows them to write whatever they will (as for whether they write well or write poorly, let another judge). Yet when a person does this, they miss out on a great opportunity for intellectual growth.
Throughout our lives, in diverse environments and seasons, we are subject to rule systems. Some are quite reasonable, while others less so; but they all exist for some positive purpose, and following (or not following) them yields recognizable and even predictable results. Some people navigate these systems very well, recognizing not only the reasons for obeying, but also noting when one kind of obedience would actually violate the spirit of a rule, and how to avoid that. Meanwhile other people just attempt to buck the system continually, and while they are smart enough to recognize that sometimes the rules don’t work, they fail to recognize when and why they do work.
This same kind of rule recognition and navigation is practiced when learning how to write poetry in formal meter. What at first glance appears an arbitrary and useless constraint, becomes known though practice as a structure for producing certain kinds of effects. It may still be to some extent arbitrary (for example, we might have had a predominantly accentual-alliterative style instead of an accentual-syllabic), but not entirely so (for the prosody we use flows out of the phonemic structure of the English language); and that discovery—understood fully only through practice—changes the rule system from something meaningless to something meaningful.
A new poet writes a short piece in iambic meter, then rewrites the poem in anapestic meter; and lo! they perceive how the change of one rule alters the feeling and impact of the subject matter. They write in rhymed couplets, and then attempt the same work in tercets, and behold! they discover that this, too, alters the reader’s reception of the subject. So it continues, as the developing poet explores each rule, each skill: practice and experimentation with prosody gives us an experience of discovery, which—if we will—may be applied to our non-poetic lives.
Why are our schools structured in the way that they are? Why is our news delivered to us in such a format? How do our sitcoms transmit cultural knowledge and values? What is the purpose of a joke made in the midst of a serious debate or religious or philosophical instruction? All of these questions have to do with the rules and structures of communication; and taking the time to master one form of communication, like poetry, can give you insight into the others.
Unfortunately, not everybody attains such insight—indeed, for the pretentious, writing poetry can just make you stupider instead of wiser. But the aid to wisdom is there, available to us, if we would take advantage of it.