As a person grows in purity, slowly an understanding of the difference between body and mind begins to develop. Hence, the mind becoming purified, perceives itself as an entity apart from the body. This in turn naturally leads to the question of the condition of the mind after the death of its physical encasement.

This is perhaps THE most fundamental question of religion. Nevertheless, since the dawn of religion, and human pondering over that question, diverging answers have been given. From a life in an underworld, or a continuous life as a ghost, to an everlasting heaven, or everlasting hell. Yet, as understanding grows, we need not take diverging answers to stand against each other, but can draw a picture wherein all views of afterlife ideas become explainable, all fitting into one grand picture, all complementing one another, all shedding more light on those ideas that stand beside them.

Below, there is drawn an image which, in a rough manner, is seeking to encompass the totality of possible afterlife life, or afterlife experience. The key to the comprehension of which comes, when it is realised that the condition of the mind during life indicates the condition of the mind after death. Hence we get a scheme of things ranging from the most terrible suffering and torture the mind can possibly imagine, usually referred to as hell; to the loftiest, noblest, grandest, and most divine experiences the mind can conceive of.

Starting with the human realm, the realm most familiar to us, we have a realm, cosmologically speaking midway between heaven and hell. It is a place in which we find a mixture of happiness and suffering, but also a mind that can make choices to yield or not to yield to these.

Hierarchically below this realm is the realm of animals. The animal realm is a place in which mind-states of desire and fear predominate, but with the possibility of some amount of sense pleasure.

Below that, in matters of consciousness, is the realm of ghosts. This, too, is a place wherein mind-states of desire and fear predominate, but much more intensely so. Ghosts are beings who are entirely caught up in their specific suffering. Although they do posses senses, little else is received through them.

The lowest of these is called the Realm of the Four Great Kings (Cātummahārājikā). It is a realm of earth bound deities, which are said to be more powerful, but not necessarily more virtuous or intelligent than human beings (although they will have at least one virtue in which they excel).

While at the very bottom of things, we have the hell realm. The hell realm stands indeed for suffering itself. Much more may not need to be said about it.

Yet, moving upwards again, we come to the brighter side of existence. In buddhist cosmology, there are 6 (sense-sphere) heavens, towering one above the other, and representing a hierarchy of virtues.*

Secondly, we have the Tavatimsā devas†, who distinguish themselves especially through a high moral nature, usually attained through selfless service.

The third realm is the Realm of the Yāmā devas. These posses (apart from a high moral nature and so on✦), high judgment qualities regarding what is objectively (morally), good and right, and what is morally wrong. That is, they posses insight into cosmic laws (esp. the law of kamma). They also seem to have a certain responsibility towards the realm of ghosts and the beings in hell; that is, although they can not directly interfere with the law of kamma, their role seems to be similar to a judge of the dead✢.

The realm above this is the Tusitā realm. It is the realm where a “Buddha to be” dwells before he takes birth as a human in order to become a Buddha. But taking things more universally, it is the realm in which most of those who become distinguished saints on earth, such as founders of religions, will dwell before they take birth as humans to fulfill their mission. Thus, the beings in this realm are distinguished not only by a high degree of insight into the nature and results of good and evil, but also possess great wisdom as to how to help beings to attain a higher mode of existence.

The fifth realm upwards, is the Nimmānaratī realm, the realm of devas who create. Following the scheme of an ever broadening consciousness, we may contrive that these may be concerned with certain creative processes regarding the planet as a whole.✧ That is, although working with natural law, they may work out schemes and plans as to how animal species in the process of evolution should turn out, how human races should look like, perhaps, how far a certain civilisation may advance before being succeeded by the next one, etc.‡ And they may, too, use their creativity in moulding the sense-sphere heavens below them, especially in the beginning stages of a planet.

While the last and highest of the (sense-sphere) heavens, is the realm of the Paranimmita-vasavattī devas✽, “the devas who control the creation”. These, following the scheme further, wield a certain power over the world and its inhabitants.☩

Higher than the heavens, is the world of Brahma, a being of pure light∯. Brahmas by their nature, are dedicated to the purification of mind. They usually do not posses the ordinary five senses (although they might be able to create such at will
for themselves), but are living purely in a world of light or energy (a fine-material world).

Beyond that, live the beings called Arūpa Brahmas. These are Cosmic Brahmas (Cosmic Gods). The lowest kind of these is of a nature of boundless space, the one hierarchically above, of consciousness, which is superseded by beings that are identified with void (or no-thingness) itself, while on the highest or most rarified plane of this scheme are said to be beings whose nature it is to be in a condition of “neither perception nor non-perception” (or “neither being consciousness, nor not consciousness”). About these, we can not say much. But following the scheme of a hierarchy of consciousness, we may contrive that although the nature of the Brahma of the first kind is boundless space, his object of perception might be the content of that space, hence the content of the cosmos, which he will be thinking and contemplating about. The nature of the second Arūpa Brahma is consciousness itself, but the object he contemplates, we may contrive to be the wholeness of space, with, or without the cosmos it contains.✿

Footnotes:

* This is not clearly worked out in the traditional texts, but I am trying my best to draw a meaningful picture that is faithful enough to the traditional scheme.

† A deva is a being similar to the angels in the abrahamic religions or the gods of the pagan pantheon.

✦ The higher devas will surpass those below them. Thus, they will not be lacking in good qualities those below their realm possess. 

✢ A judge in the human realm also can not interfere with or create laws, but he weighs out the different aspects of a case. 

✧ The texts themselves do not give us any information regarding their function. 

‡ Their life-spans is said to be many billions of years, so what to humans might look like an exceedingly long, arbitrary process might for them be just like the necessary kneading of the dough before they can get a pizza.

✽ The word "para-" in the word-compound may mean either "other /another" or "higher". The second rendering is the preferred one for the author, as it would then add up to "Beings who wield control over the higher part of creation". The "higher part of creation" in this case would mean, anything from humans upwards (viz. the human world and the deva realms). The word creation in this case will be due to the adoption of the name from pre-buddhist times.

☩ Although, they are generally not likely to concern themselves with individuals, but rather, usually perceiving a century or even millennium in a blink of an eye, they will for the most part, control or manipulate things on a vast scale. 

Some further footnotes to the Sense-sphere heavens: According to Buddhist Cosmology, demons or "anti-gods" (asuras) are classed under the same category as the sense-sphere gods. This is because they possess greater power and often greater knowledge than those beings below them. Thus, they are considered as beings of the lower heaven realms. In their case, they were distinguishing themselves through training rather in 'anti-virtues', as those on the dark path of black magic. Yet, there is also mentioning in some texts of a plane for demonic beings below the realm of ghosts. 

∯ I use here deliberately the singular form, although in Buddhist cosmology it is emphasised that there are countless Brahmas, but it too is stated, that a Brahma wields power over (at least) one world (in Buddhism called a world system, which might perhaps be equivalent to a modern days sun-system). Thus, there is a giant difference in scale in the traditional texts. It, too, is meant to indicate that it is not as easy a place to attain to as some (who usually did not try much) seem to imagine. 

✿ The main complication in this scheme comes from the "Sphere of neither perception nor non-perception", which is said to be the transcendence of the sphere of nothingness. In an "origin of the world" scheme (from which this scheme is likely to have been derived) we can easily make sense of a sequence of: a consciousness (slowly growing into infinity) arising out of the void (sphere of nothingness) and with time conceiving a cosmos (infinite space), which gradually will be filled with finematerial Brahmas. The complication with the sphere of "neither perception nor non-perception" is, that perception is generally understood to be a function of consciousness, which would fit this sphere at best into the space between the "Sphere of Voidness" (or nothingness) and the "Sphere of the infinity of consciousness". The author still works on solving the riddle.

Second Note: A Dhammatalk giving a more detailed explanation about the Planes of Existence can be found in the Dhammatalks section.