There can be little mystery in what I think about badly conceived and ill-written crime fiction that, in what I may now say is my vast experience, tends to find its most virulent forms in cozy books, most frequently (but, alas, not exclusively) in paperback originals.

Having little filter between my brain and my mouth (or keyboard), my opinions have flowed freely, on these pages and elsewhere. Although it is an opinion about a type of book, one would think, with the extremity of the mail I’ve received, that I’ve advocated genocide, the extermination of puppies and kittens, or smoking. You wouldn’t believe some of this mail. Wait, maybe you would. Especially those reading this column who wrote those letters.

What seems somehow to have been missed is the fact that I don’t despise cozy mysteries.

I despise bad cozy mysteries. I love “The Woman in White” (and can’t wait to see the musical, fingers crossed that my all-time favorite mystery novel hasn’t been embarrassed with a mediocre or worse transformation to the stage), which is certainly cozy, in that it does not contain explicit sex, violence, or offensive language.

I love Sherlock Holmes. I used to love Agatha Christie and John Dickson Carr and other writers of the so-called golden age between the two World Wars, but I’ve read them all. I proudly published Ellis Peters, Parnell Hall, Aaron Elkins, Elizabeth Peters, Edward D. Hoch, Margaret Maron, and Peter Lovesey, among others – all of whom have won or been nominated for Agatha Awards at the Malice Domestic convention.

But Holmes, Hercule Poirot, Gideon Fell, Brother Cadfael, and the other protagonists of these books were never outsmarted by their household pets, cliches did not abound, and much of the writing sparkled. Most cozy writers today have van Gogh’s ear for dialogue, with a sense of literary style that may kindly be described as somewhere between pedestrian and contemptible.

Which brings me to one of my favorite writers, whose books are so sweet that they make your teeth ache. Alexander McCall Smith introduced himself to the world of crime writing with “The No. 1 Ladies’ Detective Agency” (Anchor, 256 pages, $12.95), one of the most charming books of the decade. While much of the detection would not cause fits of jealousy among the super-sleuths of mystery fiction, the sense of the people and locale is relentlessly fascinating.

Precious Ramotswe starts her own business, which happens to be the first private detective agency on the edges of the Kalahari, Botswana. Her main training comes from a mail-order detective manual and the collected works of Agatha Christie. The crimes committed in her little village are generally lacking in violence yet are compelling to the clients who seek her wisdom and assistance, which she dispenses with equal generosity.

Four books about Mma (a term of endearment, much like mama, as she often is called) Ramotswe followed this gem, and then Mr. McCall Smith began a new series about the Sunday Philosophy Club, the second of which, “Friends, Lovers, Chocolate” (Pantheon, 260 pages, $21.95), was recently released.

Set in Edinburgh, where Mr. Mc-Call Smith now resides (he was born in Rhodesia, now known as Zimbabwe), the locale may not be quite as exotic, but the heroine, Isabel Dalhousie, is no less wise than her African predecessor. “Friends, Lovers, Chocolate” has the pace of a Victorian three-decker, only slightly livelier than Henry James. If you want action, speed, quick cuts, crisp and snappy dialogue – well, then, you’ll need to look elsewhere.

What you can expect is a geniality and evident love of humanity that would make Mother Teresa seem misanthropic. The closest to an unkind word I could find in the 260 pages of thoroughly delightful text was for the European Union, which was so aptly described as “that vast pettifoggery.”

Isabel meets Ian, a young man who has had a heart transplant. What appears to him to have come with the heart is a memory of its former owner, whom he is not permitted to know. This leads to an examination of the notion of cell memory, the idea that memory may be contained in organs other than the brain. Ian’s most disconcerting memory is of a man’s scarred face, which pops up at frequent intervals.

When Isabel decides to identify the heart donor, she learns that it was a 22-year-old man who had been the victim of a hit-and-run accident – if it was an accident. When the boyfriend of the victim’s mother matches exactly the description provided by the recipient, it seems too much of a coincidence to Isabel.

As she conducts her leisurely investigation, she pauses to have numerous cups of coffee with her niece Cat; Tomasso, the young man who is madly in love with Cat (and for whom, perhaps inappropriately, Isabel yearns, though she also regards him as her best friend); and Ian of the new heart.

Conversations meander about ethics, with much quoting of poetry, especially Auden and Burns, various philosophical conundrums, and even some metaphysical quandaries. The gentle wisdom of the author, channeled through the kindly Isabel, allows an acceptance of ideas and life choices to which many others would be closed.

What saves this from being treacly is a powerful moral sensibility that is inclusive but does not permit moral relativism. While it is abundantly clear that Mr. McCall Smith (as well as his alter ego, Isabel Dalhousie) has a big heart and a benign understanding of the human condition, he remains morally sound – as honest as a professor who would give a D to a cheerleader.

Mr. Penzler is the proprietor of the Mysterious Bookshop in Manhattan and the series editor of the annual “Best American Mystery Stories.” He can be reached at openzler@nysun.com.