In The Ten Levels of Mind, Kobo Daishi summarized the stages by which a mind develops from the most basic animalistic level to the knowledge of the true nature of the universe. He wrote it at the request of Enperor Junna in 830. The Emperor had called on each Buddhist sect to present a summary of its teaching.

The essay takes as its starting point a passage in the Mahavairocana sutra that says enlightenment consists of knowing the mind as it really is. He then sets out the stages of the spiritual development of the mind from base, animal instinct to full realization of ultimate reality.

1 The Animal Mind

In the first level, your mind is like that of an animal. You are driven by instinct and desire. Your only cares are to satisfy the hungers of your body.

2 The Basic Ethical Mind

In the second level, you begin to think ethically. You moderate your eating, saving some food to share with others and taking delight in helping in this way. You don't discriminate between friends and strangers, but you gradually come to feel fulfilled, respecting others and gaining their respect.

3 The Mind that Hopes for Heaven

In the third level, the mind hopes to be reborn in heaven. There, it believes, it will find peace.

4 The Mind That Understands That There Is No Permanent Ego

At the fourth level, the mind sees the world as a product of the senses. It realizes that perceived objects have no substance and that there is no permanent ego. Everything is transient. This level of mind Kobo Daishi associates with those who listened to the preaching of Shakyamuni.

5 The Mind Freed From The Necessity of Rebirth

At the Fifth level, the mind has mastered the twelve links of causation. The seed of ignorance has been extirpated, and rebirth is no longer necessary. Kobo Daishi associates this level with the pratyekabuddhas of Hinayana Buddhism.

6 The Mahayana Mind

At the sixth level, the mind recognizes that all phenomena are shadows of the mind itself, and compassion for all beings arises spontaneously and unconditionally. Kukai relates this level to the doctrines of the Hosso (Yogacara) school of Buddhism, which explains the samadhi of Maitreya Buddha.

7 The Mind That Understands the Unborn Nature of Mind

At the seventh level, the mind understands the Eightfold Negation of the philospher Nagarjuna. He taught that all possibile qualities of existence are equally void. The Eightfold Negation is: unborn, imperishable, unceasing, nonconstant, nonidentical, not different, not going away, and not coming. Kobo Daishi relates this stage to the samadhi of Manjusri Bodhisattva.(Japanese Monju)

8 The Mind In Harmony With the One Way

Kobo Daishi relates this level with the Chinese T'ien-T'ai school of Buddhism and the Lotus Sutra. It embodies the samadhi of Avalokitesvara.

9 The Profoundest Exoteric Buddhist Mind That Is Aware of Its Nonimmutable Nature

Kobo Daishi realtes this level to the Avatamsaka sutra and the Chinese Hua-yen school. It is the level of the doctrine of interpenetration, often illustrated by the image of Indra's net, with its infinite number of mirrors each reflecting all the others.

10 The Glorious Mind, the Most Secret and Sacred

The tenth stage embodies the mind of the Dharmakaya Buddha, Mahavairocana. We are not mind and body but Body/Mind, which is part of the Body/Mind of Mahavairocana, which is the ultimate reality.