Thoreau's contemporaries found him difficult during his lifetime, and readers have been finding his book Walden difficult ever since he wrote it.

Even describing it isn't easy. To call Walden a book about a man who lives in a cabin by a pond is even more inadequate than to call Moby-Dick a book about a man who is hunting a whale. Walden is a book about life and how it should be lived. It is difficult not only because it is knotty, erudite, full of sly jokes and sophisticated wordplay, but because it questions us about our lives in ways we are likely to find uncomfortable.

For reasons like these, many people never read it, or never finish it. This is a shame, because Walden rewards patient readers not only in the beauty of its language but in the encouragement it gives us to follow our own course — or as Thoreau put it in one of his most famous phrases, to march to the beat of a different drummer.

For those of us who love Thoreau, it is exciting to have more of his work to read. But for those who are curious about him, Letters to a Spiritual Seeker is an excellent introduction to his work.

Not all great writers write great letters. Faulkner's letters are dull and businesslike, while Tolstoy's are dull and didactic. But Thoreau's letters, like his Journal, are of a piece with his published work: they could come from no other mind. These letters are full of turns of phrase that remind you of those in Walden, but the language here is quicker, more informal and playful.

Introduced and annotated with graceful commentary by the editor, these letters contain passages as concentrated and pungent as anything in his work. “Probe the earth to see where your main roots run,” Thoreau advises. “Do what you love. Know your own bone; gnaw at it, bury it, unearth it, and gnaw it still.” Yet he is quick to point out that he cannot live up to all his own ideals. “These things I say; other things I do,” he confesses. “I am too easily contented with a slight and almost animal happiness. My happiness is a good deal like that of the woodchucks.”

Thoreau's essays on friendship (one of these, sent as an enclosure, is reprinted here) set such demanding standards of complete frankness and high-mindedness that one wonders whether Thoreau ever actually had a friend. These letters make it plain that he could in fact be a warm and attentive friend.

H.G.O. Blake, to whom these letters were written, seems to have been a nearly ideal listener. Most of his own letters have been lost, but describing Thoreau's letters to someone else he sounded much like Thoreau himself. Rereading the letters, he says, he finds new significance in them each time, “so that in a sense they are still in the mail, have not altogether reached me yet, and will not probably before I die.”