{"id":813,"date":"2026-07-07T08:00:00","date_gmt":"2026-07-07T00:00:00","guid":{"rendered":"https:\/\/minhlydao.org.vn\/en\/?page_id=813"},"modified":"2026-07-07T08:00:00","modified_gmt":"2026-07-07T00:00:00","slug":"minh-ly-yeu-giai-chapter-2","status":"publish","type":"page","link":"https:\/\/huyencong.minhlydao.org.vn\/index.php\/en\/doctrine\/minh-ly-yeu-giai-chapter-2\/","title":{"rendered":"Minh Ly Yeu Giai – Chapter 2: Why Must One Illuminate One’s Rational Nature?"},"content":{"rendered":"

WHY MUST ONE ILLUMINATE ONE’S RATIONAL NATURE? – BY WHAT METHOD? – THE PURSUIT OF KNOWLEDGE AND LEARNING<\/strong><\/p>\n

CHAPTER TWO<\/p>\n

I. WHY MUST ONE ILLUMINATE ONE’S RATIONAL NATURE?<\/strong><\/p>\n

It has already been said that Rational Nature (Ly Tanh) exists naturally within us \u2014 so why can it not be perceived, and why must one work to illuminate it? Although Rational Nature is innate, it is difficult to perceive for two reasons:<\/p>\n

RATIONAL NATURE IS OBSCURED<\/strong><\/p>\n

The Book of Changes, in its Appended Remarks (He Tu), states: “Nhut am, nhut duong chi vi Dao. Ke chi gia thien da, thanh chi gia tanh da. Nhan gia kien chi vi chi nhan, tri gia kien chi vi chi tri. Ba tanh nhut dung nhi bat tri, co quan tu chi dao tien hi<\/em>,” meaning: The alternation of yin and yang is called the Dao. What issues from it is goodness; what it completes and forms is nature. Those of benevolence, seeing it, call it benevolence; those of wisdom, seeing it, call it wisdom. The common people use it daily without knowing it \u2014 hence the Dao of the noble person (junzi) is rarely encountered.<\/p>\n

This means: the Dao necessarily involves both yin and yang, yet yin and yang are but a single circulating energy. When this one energy moves and produces yang, there is nothing that is not good. But once it becomes still and produces yin (taking on form), nature becomes constrained and partial views arise. Thereafter, each person speaks only of what they themselves perceive. Because perceptions differ, various names are given \u2014 “benevolence,” “wisdom,” and so forth \u2014 merely for ease of understanding. It is like a person viewing the world through tinted glasses: whatever color the lens is dyed, the world appears in that same color, though in truth the world itself has no such color at all. All people do likewise, day after day, without perceiving the truth \u2014 and so the Dao of the noble person is very rarely encountered.<\/p>\n

The Perfected One Thai Huyen Chon Nhon wrote a poem as follows:<\/p>\n

Before one’s parents gave birth, a single spark of numinous light,<\/em>
\nIts numinosity is lost only once form has been formed.<\/em>
\nOnce form is formed, it wraps and dims the seed of bright light,<\/em>
\nRelease all \u2014 and it remains, as before, utterly pure.<\/em><\/p>\n

Vietnamese rendering:<\/p>\n

Before parents give birth, there is a spark of the numinous (that is, Rational Nature),
\nIts numinosity ends once it has coalesced into form (the physical body).
\nOnce formed, it becomes wrapped and covers over its own radiant seed,
\nRelease everything (desires and attachments), and it remains just as pure as before.<\/p>\n

Following the order of generation and transformation, once a human being takes form, Rational Nature becomes obscured by material temperament (khi chat), causing it to become temporarily dim. The Confucians call this material nature “material desire” (vat duc) or “endowed temperament” (khi bam); Taoists call it “deluded sentiment” (vong tinh); Buddhists call it “ignorance” (vo minh).<\/p>\n

When it is said above that Rational Nature is only temporarily dimmed, this is because its original substance is utterly luminous, and nothing can cause it to permanently lose that luminosity. It is like the sun being briefly obscured by clouds \u2014 once the clouds pass, the sun shines forth again as brightly as before.<\/p>\n

Because Rational Nature is obscured, its judgment loses its universal character and lacks central rectitude. As a result, it perceives only a part while forgetting the whole; it knows only how to act selfishly, even when this causes harm to those around it.<\/p>\n

The denser the material temperament, the more heavily Rational Nature is obscured \u2014 and this is why human understanding exists at so many different levels. Thus, although Rational Nature is fundamentally equal in all (what Buddhists call the “root wisdom,” can ban tri), the resulting understanding varies greatly from person to person.<\/p>\n

RATIONAL NATURE IS EXTREMELY SUBTLE<\/strong><\/p>\n

The Book of Documents (Kinh Tho) states: “Nhon tam duy nguy, Dao tam duy vi<\/em>,” meaning: The human heart-mind (belonging to form and material energy) is most precarious, while the heart-mind of the Dao (belonging to principle and righteousness) is most subtle and faint.<\/p>\n

The “most precarious heart-mind” refers to the obscured nature spoken of above, from which all transgressions arise. The “heart-mind of the Dao,” however, is precisely Rational Nature.<\/p>\n

One cannot perceive Rational Nature through the senses \u2014 by hearing, seeing, or touching. Words and writing, belonging to form and matter, can scarcely describe it accurately.<\/p>\n

Confucius said: “Du duc vo ngon<\/em>,” meaning: “I wish to say nothing.” This was not because he truly did not wish to speak, but because it is genuinely difficult to describe the form of the Dao. When it can be spoken of at all, only its marvelous function can be described.<\/p>\n

Master Tzu Kung (Tu Cong) said: “Phu Tu chi van chuong kha dac nhi van da, Phu Tu chi ngon tanh du Thien Dao, bat kha dac nhi van da<\/em>,” meaning: The Master’s teachings on literature and refinement can indeed be heard, but his words on Nature and the Way of Heaven cannot be heard.<\/p>\n

Lao Tzu said: “Dao kha dao, phi thuong Dao. Danh kha danh, phi thuong Danh<\/em>,” meaning: The Dao that can be spoken is not the eternal Dao. The name that can be named is not the eternal Name.<\/p>\n

Master Chuang Tzu (Trang Tu) said: “Thuc vo ngon, ngon vo thuc<\/em>,” meaning: Truth cannot be put into words; what is put into words is not the truth.<\/p>\n

The Buddha said: “Thi co nhut thiet phap, tung bon di lai, li ngon thuyet tuong, li danh tu tuong, li tam duyen tuong\u2026<\/em>,” meaning: Therefore all dharmas, from their very origin until now (referring to the fundamental substance, Buddha-nature, True Suchness), remain forever apart from the characteristics of speech, the characteristics of names and words, and the characteristics of mental conditioning.<\/p>\n

Thus, even a person who has perceived Rational Nature may find it exceedingly difficult to teach another to perceive it in the same way. For Rational Nature is formless, and “seeing” it here does not mean seeing with the ordinary physical eye. Rather, it means perceiving it within one’s own heart-mind, like a flash of lightning that appears and vanishes instantly \u2014 in other words, seeing with the “eye of the mind” (tam nhan).<\/p>\n

Because of how difficult it is to perceive and know the heart-mind of the Dao, the disciple Yen Hui (Nhan Hoi) said: “Chiem chi tai tien, hot dien tai hau<\/em>,” meaning: No sooner have I glimpsed it before me, than suddenly it is behind me.<\/p>\n

Therefore, the student of the Dao, having heard the teacher’s instruction, must engage in genuine practice in order to perceive even a little of it. This is the meaning of the classical saying: “Dan nhi bat phat, di dai hoc gia chi tu dac<\/em>,” meaning: To draw the bow without releasing the arrow, awaiting the student to shoot it for themselves. Apart from this process of self-realization and self-verification, there is no other path.<\/p>\n

II. BY WHAT METHOD DOES ONE ILLUMINATE ONE’S RATIONAL NATURE?<\/strong><\/p>\n

One must practice investigating things<\/em> (cach vat) and extending knowledge<\/em> (tri tri). These are the two marvelous methods for removing the veil over Rational Nature and causing it to appear clearly.<\/p>\n

The Great Learning (Dai Hoc) lists eight items, the first two of which are: Investigating things, extending knowledge<\/em>. These are not merely the initial steps of practice, but the two essential keys of the true Dao. All other practices are subordinate to them.<\/p>\n

INTERPRETATIONS BY COMMENTATORS ON THE GREAT LEARNING<\/strong><\/p>\n

According to Master Chu Hsi’s (Chau Tu) interpretation, investigating things and extending knowledge<\/em> means: “Tuc vat cung ly<\/em>,” that is, to examine each thing directly in order to trace its principle to its ultimate root (since every thing possesses its own principle). In other words: to study and research each thing in order to broaden one’s knowledge. This is seeking principle externally, and may be called “broad knowledge” (quang tri) \u2014 that is, understanding that is abundant and wide-ranging.<\/p>\n

According to Wang Yang-ming’s (Vuong Duong Minh) interpretation, investigating things<\/em> means “Cach chanh su vat<\/em>,” that is, to correct and rectify each matter, making it upright and good. He held that the meaning of the word thing<\/em> (vat) is very broad, not limited to physical objects alone. Wherever one’s intention is directed \u2014 regardless of whether that object has physical form or not \u2014 it is called a “thing.” As for extending knowledge<\/em>, according to him, this means developing one’s innate conscience (luong tri), causing it to grow ever more luminous, until it shines everywhere, leaving no place in darkness.<\/p>\n

THE TRUE MEANING ACCORDING TO MINH LY DAO<\/strong><\/p>\n

Master Chu Hsi’s interpretation leans toward knowledge, resembling modern science. Wang Yang-ming’s interpretation emphasizes the distinction between good and evil, closer to ethical theory. The Dao, however, transcends both the sciences and ethics. Thus, while both interpretations have their merits, neither has fully expressed the intent of the ancient Sages.<\/p>\n

In our humble view, cach<\/em> means to block, to reject, to detach oneself (se detacher). Investigating things<\/em> means not allowing external things to govern one’s heart-mind, but constantly resisting greedy desires and improper habits. Written out in full, this is cach vat duc<\/em> \u2014 that is, eliminating the desire that follows after material things.<\/p>\n

Although the meaning of the word thing<\/em> is broad, as explained above, it must first be understood as referring to wealth and goods (tai hoa). The Record of Music (Kinh Nhac Ky) states: “Vat chi cam nhon vo cung, nhi nhon chi hao o vo tiet, tac thi vat chi nhi nhon hoa vat gia da, diet thien ly nhi cung nhon duc gia da<\/em>,” meaning: Things affect people without limit; and if people’s likes and dislikes have no restraint, then when things present themselves, people inevitably become transformed by them (that is, swept along by things). When a person becomes transformed by things, Heavenly Principle (that is, innate conscience) dies out, and human desire runs rampant.<\/p>\n

If the heart-mind clings to attachment to any thing, then innate conscience becomes obscured by that thing. At first, innate conscience chases after the thing; in the end, the thing eclipses innate conscience entirely. The power of external things and the power of innate conscience stand opposed to one another \u2014 one must prevail, the other perish; they cannot coexist. If one casts aside things, one gains innate conscience; if one clings to things, one loses innate conscience. Therefore, in order to extend knowledge<\/em>, one must first investigate things<\/em>.<\/p>\n

To extend knowledge means to develop innate conscience, causing it to become completely luminous. What better way to extend knowledge than through careful reflection and examination, tracing one’s original nature \u2014 innate conscience \u2014 to its very root? If one merely follows old habits (nhan tuan) and examines things through the lens of the ego (that is, material temperament), one can never attain liberation, and will remain caught within the bonds of material desire until death.<\/p>\n

Master Shao Yung (Thieu Nghieu Phu) said: “Di vat quan vat, tanh da; di nga quan vat, tinh da. Tanh cong nhi minh, tinh thien nhi am<\/em>,” meaning: To observe things through things (maintaining an objective standpoint) is to observe through nature; to observe things through the self is to observe through sentiment. Nature is impartial and hence luminous; sentiment is partial and hence dark.<\/p>\n

These passages from the Confucian classics cited above sufficiently confirm the true meaning of investigating things and extending knowledge. Taoism calls this: Hu tam thuc phuc<\/em> (emptying the human heart, filling the heart of the Dao). Buddhism commonly says: Gia tinh bieu duc<\/em> (restraining desire and sentiment, manifesting virtue).<\/p>\n

INVESTIGATING THINGS AND EXTENDING KNOWLEDGE HAVE MANY LEVELS<\/strong><\/p>\n

According to Wang Yang-ming, the extension of innate conscience may be divided into four levels:<\/p>\n