到了19世紀末期，具有多種多樣表現形式的男女的“性（sexuality）”[1]已經成為了科學研究的對象。確切地說，人們逐漸到處可以見到“性（sex）”的存在。然而，與此同時，他們自己也發現描述感官欲望或性欲望的辭彙量大大地減少了。在中世紀的英國、法國、西班牙、義大利和德國，表達性器官、身體機能和做愛（lovemaking）的那些古怪的詞語，已經逐漸被一些使人窘迫的委婉詞語和讓人不能理解的大量希臘與拉丁術語所替代。豐富的本國辭彙被“粗俗”而“下流”的外國辭彙所壓制。

到了克拉夫特-埃賓在他的出生國出版自己的著作《性病態》（Psychopathia sexualis，1886）[2]的時候，“能夠讓人容忍”的涉“性”的詞語就已經變得少之又少了，並且公眾變得如此敏感，以至於不能公開談論“性”這個話題了。為了不讓普通讀者讀懂這本書裏的內容和避免遭致可能的輿論抨擊，不僅書名本身，而且許多直露的段落都是用拉丁文寫成的。

Introduction - What is sexual behavior?

History of the Term 7

Toward the end of the 19th century, the “sexuality“ of females and males with its manifold manifestations had become an object of scientific research. Indeed, people began to see "sex" everywhere. At the same time, however, they also found themselves with a greatly reduced vocabulary for the sensual or erotic. The fantastic variety of medieval English, French, Spanish, Italian, and German words for sex organs, body functions, and lovemaking had gradually been replaced by some embarrassed euphemisms and a small number of incomprehensible Greek and Latin terms. The rich vernacular was suppressed as "vulgar" and "dirty".
By the time Krafft-Ebing published his study “Psychopathia Sexualis” in his native German, the “acceptable” language had become so impoverished and the public had become so sensitive that one could no longer talk openly about the subject of “sex”. Not only the title of the book itself, but also many explicit passages were written in Latin so that ordinary readers could not understand them and perhaps take offense.