Shojin Ryori was brought into Japan via China and Korea together with the introduction of Buddhism. It has settled into the Japanese way of cooking, different from China or Korea, and developing its own unique cooking style with practical and refined skills.
It is commonly said that Japanese cooking differs from Western cooking in the basis of "cooking with water" against "cooking with fat". In other words, the difference may come from the geographical condition whether it is a continent or an island.
Vegetables, especially soy beans and nuts are the main ingredients and these are prepared according to the season; In spring, the new sprouts that shoot out, in summer, the well grown green leaves, in autumn the nature blessed fruit and nuts, and in winter, roots that warm the body from the core. In this manner, without going against seasonal ingredients, the menu is naturally made out.
In Buddhism, "Retribution" is firmly believed and because of the conception that all things of nature have life, Shojin Ryori prohibits eating meat and it is considered virtue to make the most of vegetables and beans.
The word "Shojin" means a devotion to pursue a perfect state of mind banishing worldly thoughts and making efforts to keep striving for limitless perfection at each stage. That is to say, to prepare Shojin Ryori itself is a part of practice of Buddhism.
The present-say perception of Shojin Ryori, in general, refers to a vegetarian diet although this is only a narrow interpretation after considering the Buddhism background.
Up to the early twentieth century, the Japanese dietary habits have been unified with nature, and both vegetables and animal meat have been included in their daily food.
However, the more the western style of cooking gets popular in modern times, the less the idea of Shojin Ryori became. Nevertheless, Japanese cooking gets worldwide attention these years in terms of offering healthy and well-balanced meal, and Shojin Ryori is recognized as one of that ideal style.
Note: a definition in encyclopedia
Type of vegetarian cooking introduced into Japan together with Buddhism in the 6th century. Shojin is a Buddhist term that refers to asceticism in pursuit of enlightenment, and ryori means "cooking." In the 13th century, with the advent of the Zen sect of Buddhism, the custom of eating shojin ryori spread. Foods derived from soybeans - including TOFU - and vegetable oils - including sesame, walnut, and rapeseed - were popularized in Japan as a result of their use in shojin ryori.