“If you are as interested in sex as you say you are, there is a really lovely book about it in my study — on a top shelf. It’s red, and it’s called The ABZ of Love,” Kurt Vonnegut wrote to is wife Jane in a 1965 letter published in the fantastic new volume Kurt Vonnegut: Letters, and he signed, “Love from A to Z, — K”. Naturally, I went hunting for the obscure vintage tome, which turned out to be as kooky and wonderful as Vonnegut’s recommendation promises. An ABZ of Love (public library), a sort of dictionary of romance and sexual relationships covering everything from radical-for-the-era topics like birth control and homosexuality to mundanities like bidets and picnics to abstractions like disappointment and excess, was originally published in 1963 by Danish husband-and-wife duo Inge and Sten Hegeler, featuring gorgeous black-and-white sketches by artist Eiler Krag reminiscent of Henri Matisse’s Ulysses etchings.

The book is presented with the disclaimer that rather than an ABC textbook for beginners, it is a “personal and subjective supplement to the many other outstanding scientific books on sexual enlightenment already in existence,” setting out to describe “in lexical form a few aspects of sexual relationships seen from a slightly different standpoint.” Indeed, the book was in many ways ahead of its time and of the era’s mainstream, pushing hard against bigotry and advocating for racial, gender, and LGBT equality with equal parts earnestness and wry wit.

The Hegelers, who “have tried to be straightforward and frank,” write poetically in the introduction:

If we look through a piece of glass, irregularities and impurities may distort and discolor the impression of what we see. If we regard something through a convex lens, it appears to be upside down. But if we place a concave lens in front of the convex lens, we correct the distortion in the convex lens and things no longer appear topsy-turvy. Each one of us regards the world through his own lens, his own glasses. The effect of those glasses is that, even though we may be looking at the same thing, not all of us actually see the same thing. The lenses are ground by each individual’s upbringing, disposition and other factors. […] This book is neither art nor science — even though it borrows ingredients from both. It is more by way of being an extra piece of glass through which we can regard a part of life. One can slip it in between one’s own glasses and the window. It is a piece of glass we have found and polished up a bit. We have looked through it and thought the world looked a bit more human. Perhaps some will think the same as we do.

Many of the entries focus on debunking stereotypes and condemning bigotry, accompanied by apt illustrations.

Some are even outright snarky:

A delightful entry under Sense, common echoes Anaïs Nin’s timeless insight on emotional excess and reads:

Everybody talks about using common sense. Many believe that we are all basically imbued with common sense. It is said that women are creatures of emotion, but that men use their common sense. Nonsense. We are all extremely prone to be guided by our emotions in our choices, actions, judgements, etc. […] We are none of us so full of common sense as we would like to think ourselves. So there are two paths we can take: one is try to deny and suppress our emotions and force ourselves to think sensibly. In this way we run the risk of fooling ourselves. The other way is to admit to our emotions, accept our feelings and let them come out into the daylight. By being suspicious of all the judgements we pass on the basis of what we feel (and not until then) we shall taken a step towards becoming practitioners of common sense.

The Hegelers don’t shy away from the philosophical and the prescriptive:

Under Development, there’s a somewhat humorous infographic look at the stages of erotic development. We would like it to be follow a course in which “we very rapidly and regularly become cleverer and cleverer”:

We imagine it goes something like this:

In reality, however, it’s more something like this:

…after swinging around a certain point for a time, very small swings to and from in either direction, a sudden drop with the resultant feeling of hopelessness [and then] once more pendulation around one point for a time, then a drop, then that hopeless feeling, improvement again, etc., etc., without ever reaching the absolute ideal. Disappointments and depressions are necessary features of any process of learning, every development.

Among the more interesting entries is one under Personality, explaining the Freudian model of the self through a visual analogy of a Native American totem pole, with the disclaimer that personality is still an open question:

A person’s personality is the sum of all the things in a person that go to determine the said person’s relationship to other people. Many theories have been expounded concerning human personality. Many models have been made in an attempt to show what actually happens. Some of these theories are more practical than others, but none of them is correct. We still know too little — perhaps we shall never find the right one. The one which will be described here is of course not the right one either. It is the one used in psychoanalysis. This model — like so many other theories — is a picture, an attempt to explain something unknown with the help of something known. If we think of personality as the Indian totem pole with three faces corresponding to three persons it will give us an idea of the model. The three persons have names and are very different in character: 1) The top face is rather strict and censorious. A bit of a light-snuffer. We call this person the super ego, and it represents everything we have learnt concerning what is right and wrong. The super ego reminds us how to drive through traffic, how to hold a knife and fork and generally speaking how ‘one’ behaves. It is also the voice of conscience. 2) The bottom face on the totem pole is a person we call the id. This person takes care of our wishes and urges and needs — the very honest, primitive, but likewise somewhat ruthless powers with in us. The face of the id is therefore a somewhat primitive, uninhibited, wild and brutal mug. 3) The middle face is our own. It is called the ego and is a little squashed between the other two faces. While the upper face possibly resembles our parents, and the bottom face appears a little strange to us, we find it easiest to accept the middle face — a compromise between what we want to do and what we are allowed to. We are a little perplexed because if we are very good and reserved — then the bottom person thrashes his tail and rebels while the top person nods approvingly. And if we are too abandoned and let the bottom person have his own way –well, we find ourselves landed with a bad conscience, because the upper person grumbles. So we have to strike a balance. We have to stick to certain moral code — stick to certain rules of the road in order to mingle with the traffic. But we must also pay attention to our ‘nature’ — our id — who likewise demands his rights.

Both beautifully illustrated and boldly defiant of its era’s biases, An ABZ of Love is, just as Vonnegut assured his wife, absolutely wonderful.