supposedly comes from the characters くノ一 (respectively hiragana ku, katakana no and kanji ichi), which make up the three strokes that form the kanji for "woman" (女). In fiction written in the modern era kunoichi means "female ninja". In the Western world, the word ninja became more prevalent than shinobi in the post–World War II culture, possibly because it was more comfortable for Western speakers. In English, the plural of ninja can be either unchanged as ninja, reflecting the Japanese language's lack of grammatical number, or the regular English plural ninjas. History Despite many popular folktales, historical accounts of the ninja are scarce. Historian Stephen Turnbull asserts that the ninja were mostly recruited from the lower class, and therefore little literary interest was taken in them. The social origin of the ninja is seen as the reason they agree to operate in secret, trading their service for money without honor and glory. The scarcity of historical accounts is also demonstrated in war epics such as The Tale of Hōgen (Hōgen Monogatari) and The Tale of the Heike (Heike Monogatari), which focus mainly on the aristocratic samurai, whose deeds were apparently more appealing to the audience. Historian Kiyoshi Watatani states that the ninja were trained to be particularly secretive about their actions and existence: However, some ninjutsu books described specifically what tactics ninja should use to fight, and the scenarios a ninja might find themselves can be deduced from those tactics. For example, in the manuscript of volume 2 of Kanrin Seiyō (間林清陽) which is the original book of Bansenshūkai (万川集海), there are 48 points of ninja's fighting techniques, such as how to make makibishi from bamboo, how to make footwear that makes no sound, fighting techniques when surrounded by many enemies, precautions when using swords at night, how to listen to small sounds, kuji-kiri that prevents guard dogs from barking, and so on. Predecessors The title ninja has sometimes been attributed retrospectively to the semi-legendary 4th-century prince Yamato Takeru. In the Kojiki, the young Yamato Takeru disguised himself as a charming maiden and assassinated two chiefs of the Kumaso people. However, these records take place at a very early stage of Japanese history, and they are unlikely to be connected to the shinobi of later accounts. The first recorded use of espionage was under the employment of Prince Shōtoku in the 6th century. Such tactics were considered unsavory even in