[The poems of The Colossus show that] Miss Plath has some of the excusable faults of youth: the attempt to blow up the tiniest personal experience into an event of vast, universal and, preferably, mythic importance; intoxication with the rare word which she displays with nouveau riche ostentation; and obsessive fiddling with certain forms and devices, e.g., terza rima. But with time—the deepening of perception and strengthening of control—these temporary improprieties can become the proper pursuits of poetry: holding nature's immensities in the poem's pocket mirror; redeeming the language; and letting the parallel rails of form lead on to a meeting point in, and with, infinity. When Miss Plath resists pretentiousness, she achieves glistening, evocative poems….

John Simon, "More Brass than Enduring" (originally published in The Hudson Review, Vol. VX, No. 3, Autumn, 1962), in his Acid Test (copyright © 1963 by John Simon; reprinted with permission of Stein...