It's always dangerous to review a work of satire- too much analysis can kill the humor, and there's nothing funny about a dead clown.
So rather than trying to approach this book as humor, I think it is useful to understand this short work by Erasmus from the perspective of joy. The Praise of Folly simply drips with delight in creation. We see that even in the title, this is a work of 'praise.' Erasmus gives us a light-hearted spoof of those who have no sense of humor and continually take themselves, their professions, and the world entirely too seriously. We all know someone like that- and if you don't, the odds are that es homo.
Erasmus really spares no one- scientists, artists, businessmen, soldiers, merchants, etc all feel the weight of his pen. Anyone and everyone who has ever said "but what I do is of the utmost importance, and never to be treated lightly" gets a jab in the ribs from the narrator, the goddess Folly. Consider her words to one group near and dear to my own heart, the college professors:
Thanks to my [Folly's] efforts, they [the professors] consider themselves the happiest of men, particularly when they can terrify their flock of trembling schoolboys with glowering expressions and thunderous voices... Meanwhile all this beastliness seems to them the height of elegance, the stuffy classroom smells of wildflowers, and their own miserable drudgery seems a royal kingdom, such as they wouldn't exchange for the supreme sway of Phalaris or Dionysus. But what raises them to the heights of ecstasy is if they discover some new point of interpretation. What they teach their students is utter gibberish, but they think their own critical discernment is far beyond that of the greatest grammarians... And, though I don't know by what flim-flam they do it, they are able to persuade the mothers and fathers of their pupils that they themselves are just as great as they make out. Another special delight they take is to dig out of some moldy old manuscript some exotic fact, like the name of Anchises' mother, or some completely obsolete word such as 'cuhyrde,' 'eperotesis,' or 'cuttlebung;' sometimes one of them comes up with a fragment of old rock carved with a few broken letters. And then, oh Lord, what elation, what cries of triumph, what tributes of praise, as if Africa had been conquered or Babylon put to sack. (51-52)Anyone who has ever suffered through an academic conference should instantly see the truth of this statement. Not that academia doesn't have its place (Erasmus himself would be the first to admit that it does), but to fail to see how quickly it can get silly is to simply prove Folly's point.
But Folly's main targets are the philosophers and theologians (remember, at this point there was basically no difference between the two). The problem with such people, Folly tells us, is that first, because they are exploring worthwhile questions, they begin to take themselves too seriously; then they get caught up in the fine points and details of those questions; and finally they end up taking the fine points and details as seriously as they took the original worthwhile questions they were working on. This process has cost them the joy that should go along with -or, heck, even result from- serious philosophical and theological inquiry. By subjecting them to the mockery of Folly, Erasmus is less-than-gently trying to remind them that wonder and delight have their proper place in the world of philosophy and theology.
And, well, take up and read for yourself- it's very much worth your time.
I should point out that I've been reading from the Norton Critical Edition of Erasmus' works, and there are a number of other pieces included that are also worthwhile. I have yet to have a bad experience with a Norton Critical Edition, and the selections included in this volume did not disappoint. Other readings included a selection of his letters (apparently the kind of writing he was most comfortable with), a selection of his dialogues, his treatise on pacifism (akin to Praise of Folly, but from the perspective of "Peace"), and his two versions of a Forward to the Latin New Testament. Of these, the Forward and the Dialogues "Julius Excluded from Heaven", "The Religious Feast", and "The Abbot and the Learned Lady" are especially good.