When the Heian period came to an end at the end of the twelfth century, the whole of Japan was swept by war between the Genji and Heike clans. Dead bodies were seen scattered all over the place. Depictions became very realistic and human portraits began to appear. These were a kind of pornography, as they depicted what people should not see. Pornography is not about the erotic but involves exposing things which are tabooed to see or think.

 Fujiwara Takanobu was an expert portrait artist. When André Malraux saw his 'Portrait of Minamoto Yoritomo' (also thought to be a portrait of Ashikaga Naoyoshi due to the clothes that are worn in the portrait) and 'Portrait of Tairano Shigemori' (Jingoji), he was wonderstruck and said, 'The Japanese could draw such realistic portraits such early in history!' The Japanese people's eye had become attuned to realistic depictions. When a realistic picture of people accompanying ex-Emperor Goshirakawa in his trip was drawn on the sliding paper door of Saishokoin in 1173, Kujo Kanezane, the prime minister at that time, wrote in his diary 'Gyokuyo' as follows: 'It is a blessing that I did not go.' What he meant was that he was glad he did not have to face the humiliation of being drawn life-like. A painter waited at court and drew realistic pictures of people going into the palace. In the 'Picture Scroll Portrait of Aristocrats', the styles of dress were fixed but the faces were drawn realistically. When people saw these pictures, they spread rumors such as 'the present emperor has a round face' and 'the present prime minister has a red nose.'

 It was taboo to talk about personal features during the Heian period and people of high birth were drawn in an impersonal manner with thin eyes and hooked nose. Hence, drawing and seeing such realistic depictions of faces and appearances constituted pornography and were considered shameful. However, this taboo was broken and portraits appeared as people who were drawn demanded to be depicted realistically with personality.

 Pornographic picture scrolls called kachie were created due to the desire to see things which should not be seen. They first appeared in the Kamakura period, but more copies were produced in the Muromachi period. There was a folk belief that women's vagina was a charm against disaster, and it was said that if a samurai carried a picture of woman's vagina to war, he would be protected from bows, arrows, swords and spears. It was thus called kachie (victory picture) that brought about victory. In this way, if pornographic pictures were called kachie they would not be censored.

 A typical kachie is a picture scroll with realistic depictions of men and women having a sex competition. A sex competition is held between men and women in court and the winners display incredible skills. Finally a woman wins and is praised by the emperor. It ends with the comment that women are stronger after all. Kachie referred to pornographic pictures until the end of the Tokugawa period, but regained its original meaning as a good luck charm for soldiers after the Meiji period.

 There were no restrictions on art in this period. Pictures called okoe also appeared. The name okoe derived from a phrase in Kabuki, 'It's rather impudent (okogamashii) to introduce oneself, but...' and meant being pushy or self-assertive. They were genres that artists would not normally draw, such as silly, comical, meaningless, or critical pictures and caricatures. These were important precursors of manga. Toba Sosho's 'Comical Picture of Birds and Beasts' is a classic example of okoe. It makes fun of Buddhism by depicting Buddha as a frog, and represents a rabbit sliding on snow and a monkey doing a high jump, thus inducing meaningless wit and laughter. These rich anthropomorphic representations of animals are inherited by manga and anime.

 In the Muromachi period, the 'book' media appeared. Picture books called 'Nara Picture Books' appeared. These consisted of pictures of picture scrolls cut up and bound into book style with alternating pages of the story in writing. A temple in Nara which published sutras tried to sell books with pictures and stories of Shutendoji (Wine Drinking Ogre) and Issunboshi (One Inch Boy) that were popular among the masses.

 They were first in the form of picture scrolls but turned into sutra style which were folded like bellows and could be spread out. The writing and pictures were separated in the latter. The paper was very bulky and it was difficult to discern the page order, so the book form appeared. With the emergence of the book form, pages had to be turned and a new kind of segmentation of information developed. It became possible to go on to a different page after reading one page, or skip pages.

 So when the book form first appeared, it must have been difficult to read because the brain was used to reading picture scrolls and the brain functions required for reading a book was different. This is a very important point. A new function of the brain developed to segment information according to opened pages due to the development of a new hardware, namely the book. This function is probably also applied in the case of reading today's manga.

　

 Natural history appeared after the development of the book form. Natural history books had pictures of items accompanied by explanations, stories about them and details of their efficacy. Natural history in Japan developed due to the country's isolation policy. Since there were basically no imports from foreign countries, people had to investigate and develop domestic products.

 During the period of Wanli Emperor in China (time when Hideyoshi was fighting in the Korean Peninsula), it was said that knowledge of natural history had to be fortified in order for China to become a strong country and Li Shizhen was employed to edit Compendium of Materia Medica. One set of this encyclopedia was imported to Japan and skillfully translated into Japanese.

 Pharmacologist Inou Jakusui wrote a complete work of natural history called Shobutsuruisan (Collection and Classification of Various Items) complementing Compendium of Materia Medica and all kinds of illustrated encyclopedias covering all Japanese products were produced. On the basis of these, minutely detailed information of various products was circulated, and made into narratives and pictures to attract people's attention, resulting in a new value being placed on such information. An exhibit of rare foreign birds was a great hit in Dotonbori in Osaka in 1758, and a foreign handbook on birds Kikanmeiwa was published. This kind of exhibit was brought together with others and synthesized into expositions. All sorts of catalogues, product pamphlets, illustrated technical manuals emerged based on Hiraga Gennai's illustrated catalogue Butsuruihinsitsu (Catalogue of Items) for the Product Exhibition of Eastern Capital in 1763. Thus illustrations, diagrams, pictorial explanations developed involving literature and the arts.

 For example, an illustrated dictionary of seasonal vocabulary in haiku was published. If we open the page on cotton flowers in the seasonal vocabulary given in Haikainanoshiori (A Guide to Vocabulary for Haiku), there is a detailed drawing of the flowers and some selected famous verses on cotton flowers. Since haiku is composed based on experience, this is a very good encyclopedia of everyday life with pictures. Haiga (picture drawn along with haiku) is also rather like a one frame manga. These enabled people to grasp information pictorially and very much increased understanding and had the effect of bringing them close at hand.

 Moreover, kyoka (comic tanka poetry) picture books illustrating kyoka appeared when kyoka became popular in Edo. Utamaro collected kyoka on birds, beasts, insects and fish and tried to publish four volumes of color editions. He eventually published 3 volumes; Ehonmushierami on insects, Shiohinotsuto on fish, and Momochidorikyokaawase on beasts. In particular, Ehonmushierami contains kyoka about insects illustrated with pictures of detailed drawings of insects which cannot be seen by the naked eye and were not depicted in ukiyoe until then. They were also full of smart humor. This was a result of a revolution in eyesight as lenses became popular and people were able to see minute details.

 The development of information technology has been turned into science fiction. Hitogokorokagaminoutsushie (Pictures Reflected in the Mirror of People's Minds) by Santokyoden, written at the end of the eighteenth century, depicts the invention of a mirror that reflects everything (imaginary peeping glasses) including the contents of people's minds. Speech balloon type lines and illustrations of situations were skillfully combined to represent a tight-rope walker being worried about falling off the rope, and a prostitute and her client having different thoughts, making the readers laugh.

 Books bound in Japanese style with pages of rather silly but witty pictures and writings were published one after another. These are called kibyoshi (illustrated storybooks with yellow covers). However, kibyoshi was banned during the Kansei Reforms as it was considered to be too frivolous, and yomihon was introduced. Yomihon was specified to be based on historical accounts of valor and loyalty approved by the bakufu. Popular writers of Edo who opposed this policy created illustrated yomihon on romances full of fantasy and wonders while adhering to the bakufu's conditions. Takizawa Bakin and Katsushika Hokusai came together as a wonderful pair and produced unique yomihon with stories and pictures mutually illustrating each other. Their representative work is Nansosatomihakkenden.

 Katsushika Hokusai published Hokusai Manga (first volume published in 1814, 15 volumes in total) which became the origin of the word manga. The word 'man' is the same as the 'man' in manyuki (light travel sketches) and manga meant pictures drawn freely without worrying about the context. Mangas are usually drawn according to a story, but Hokusai's manga is free from a predetermined story. Once a story is constructed, the scenes have to be specified and freedom must be renounced. The idea was to create plenty of free material before constructing a story so that a variety of inspiration would be born.

 Hokusai Manga was rather like a large encyclopedia or collection of illustrated data covering body and emotional representations and objects of interest and knowledge. It is incredible how a single person created such a data base. This was taken to Europe in the 1830s and greatly influenced western paintings such as those of the impressionists. Hokusai was also able to draw waves in the sea. A scientist in the forefront of research in complex systems points out that only Da Vinci and Hokusai were able to draw waves accurately. Hokusai's waves have been depicted by the free spirit of manga. Thus manga included deep insights into nature.