Life in the natural world differs from life in the spiritual world in that we are brought inevitably into contact and association with all kinds of people. By family relationship, the neighbourhood in which one lives, through travel, through social activities, through business and employment, the path of each one is continually crossing the paths of others. Such contacts may be casual and fleeting, but under the influence of mutual interests or common needs the life of one may become closely intertwined with the lives of others, and this perhaps for many years. This is true irrespective of mental states, and it may bind together externally people of extremely diverse forms of mind, disposition or temperament. From this arises a conflict of wills that may cause suffering varying from a mere momentary irritation to prolonged and severe distress of mind. Such an interplay of heterogeneous natures results from the fact that human society on earth is founded, not upon congeniality of spirit, but rather upon common needs of the body and of the material world. The uses that bind people together may be performed by the evil as well as by the good. They may be performed from love to the Lord and charity toward the neighbour or the loves of self and the world. Not only this, but in everyone evil tendencies and good tendencies exist side by side. At times they act from one, and at other times from the other. So mixed are the motives that prompt people to action, and so deeply are they concealed that no one can know with certainty whether he acts from charity or from some selfish ambition.

Conditions under which opposing affections are brought together and held in close association are not confined to individuals of an alien race or nationality, but frequently obtain among members of the same family. Such may have many interests in common, and may be bound by strong ties of affection. They may be held together by mutual responsibilities, even though they may be poles apart as to ideals of life or principles of action, and thus may be incapable of deep mutual sympathy or understanding.

In the other life this is not so. There all consociations are according to affinities of love and affection. Diversity of love spontaneously causes separation, while affinity brings presence. There are not external needs such as exist on earth to compel the association of alien spirits. The only needs that remain after death are spiritual. The uses performed for one another are all spiritual. It is in accord with these spiritual uses that society there is organized. We read in Arcana Coelestia 2449:

Such is the communication in the other life of all ideas of thought and of all affections, that goods are communicated among the good, and evils among the evil.. . Unless the good and the evil were separated, countless mischief would result, and moreover, all association together would be impossible . . . yet all things are most exquisitely consociated, in the heavens according to all the differences of love to the Lord and. . . mutual love, and of the derivative faith; and in the hells according to all the differences of cupidities and of the derivative fantasies. Be it known, however, that the separation is not entire removal, for from no one is that which he has had altogether taken away.

All who possess similar affections are, in general, together in one place, in one heaven, and in one society of heaven. So also the particular varieties of one homogeneous society also are arranged according to more particular likenesses of affection, of thought and of use. Thus in heaven the only bonds are those of love, and only those who possess a mutuality of love can be together in the same heaven, the same society, the same house. So also in the hells, those in similar loves of evil are associated, and this more closely as their loves are more nearly alike. In heaven the bond is one of mutual love and use, while in hell the bond is one of the need to enlist the cooperation of others for the sake of one's own personal ambition.

Between heaven and hell, therefore, there is “a great gulf fixed” (Luke 16:26). Those from heaven cannot pass over to those in hell, and evil spirits cannot invade the heavens. Those who are spiritually incompatible do not meet, and remain quite unaware of one another. That is because there are no external necessities compelling them to associate. This is not the case in the world of spirits, into which intermediate world every one comes immediately after death. There, for a time, the good and the evil are together very much as they were on earth. Yet, even there, spirits are not bound together by external necessities, but solely by loves and interests they have in common. Every one entering that world, unless he has been fully regenerated on earth, carries with him opposing affections by which he is brought into contact with spirits of opposing character. Each one is led by his affections to seek consociation with others of like disposition. Those who have been striving for regeneration retain many habits of thought and life, many appearances and fallacies which they mistake for the truth, and many hereditary tendencies to evil which they have not yet overcome. The converse also is true; namely, that the evil possess acquired habits of use, of charity and of piety whereby they have adapted their external lives to the demands of society. The purpose of a temporary period of life in the world of spirits is that through a series of experiences and by instruction, mistaken ideas may be corrected, and evil habits may be rejected in favour of uses in accord with one's ruling love. And on the contrary, outward pretences of good and truth may be removed that the inner character of evil may become apparent. By this means the good are gradually separated from the evil, the good being instructed and elevated into heaven, while the evil seek association with their own kind in hell.

This process may at times require a considerable period, and may be accompanied by severe temptation and suffering. But at last each one is brought, by his own will, through Divine leading, into his place, either in heaven or in hell.

The conditions existing on earth are of the Divine Providence because only by the mingling of people of different characteristics can any one learn to know himself. Only thus can one recognize the quality of evil tendencies in himself, and determine to oppose them. No one living in a mutual admiration society could realize his own shortcomings. His pride would be continually fed by the praise and approbation of others. But when he is in contact with opposing natures he is given the constant opportunity to reflect upon his own affections, to judge them, and select those which he wishes to cultivate, while rejecting those he finds objectionable. Especially in periods of spiritual decline, when evil conditions are tolerated in human society, and when the dominant loves are those of self and the world, many are bound together by external bonds who are interiorly very diverse. Families are forced to live together in single rooms or in close quarters that bring them into continual conflict with one another. They may have to live in neighbourhoods largely occupied by criminals. They may be restricted in association by conditions of war, or of political and social antagonisms. Nevertheless, even on earth everyone has a longing to associate with others who understand them and sympathize with their aims and purposes. A most important need is felt for a home where one's own family may enjoy privacy and a sense of freedom from outside pressures. Human nature, even on earth, causes everyone constantly to seek congenial companionship, and to struggle against the conditions that throw them together with those who are antagonistic and unresponsive.

That which is of particular interest to us at the moment is that the difference between conditions on earth and corresponding conditions in the spiritual world is due to a difference in the power of reflection. On earth people are compelled to reflect upon bodily needs and worldly desires, with their resultant uses. They are brought into association with others by limitations of time, and place and opportunity, by the lack of economic means, or by considerations of health, of employment or business. Such restraints often appear as unfortunate, or even cruel, and yet no one can altogether avoid them. The truth is that without them no one could regenerate. Only by such a mingling of divergent natures can one be led to perceive the quality of his own states of mind. Without some such compulsion no one would reflect upon his inner thoughts and emotions. Every one takes these for granted, and accepts them at face value unless his judgment of them is challenged. Reflection first arises when one sees these same qualities in others, and notes their effect upon himself. Not otherwise can any one overcome the bias or prejudice with which he is wont to judge himself. Concerning this we read:

When [a] man does not reflect upon those things that are in his mind or. . . [spirit,] namely, how he thinks, what he thinks, what he does, and whence he acts [he has no knowledge of these things] . . . Without reflection he knows nothing, except that a thing is.. . [He does not know] its quality. But if he reflects in himself from others, or if he suffers others to reflect upon him, and to say of what quality he is, then.. . [first] he can know that he is of such a quality. Otherwise he can never know it, but he remains in his fantasies, and from them he reflects upon others. (Spiritual Diary 734).

This is a matter of universal experience, and it is permitted by the Lord in order that we may learn to know our self, to judge as to the quality of our habitual thoughts and feelings. Judgment requires knowledge, and without knowledge there can be no freedom of choice. The whole purpose of our life on earth is that we may learn to judge between good and evil, truth and falsity, and may freely choose the one and reject the other. To this end we are compelled by circumstances to mingle with people of alien character and given the opportunity to reflect upon our own innate tendencies. Even given the opportunity, there is no assurance that someone will avail himself of it. To do so requires an act of will, and a struggle, for everyone is prone to reflect upon others rather than upon himself. Everyone naturally assumes that he is right, and that those who disagree with him are wrong. The temptation to judge others harshly, and one self with great leniency is very strong. This is especially true if one has no standard of judgment based on Divine revelation, and no religious conscience from which to judge.