In the ancient world, the wise man was often called the knower of the gods. The gods signifying hidden entities which were believed to be the controlling agents of the world. Entities which were accessible only to those who were initiated into their mysteries. In modern times too, there are wise people investigating hidden entities, only now they are designated ‘forces of nature’. The understanding of them, similar to the understanding of the gods of old, can give them certain powers over external nature. The modern means of their studies being called the ‘Sciences’. A word coming from the meaning ‘to know’.
The Buddhist Abhidhamma system being almost a blend of both, might be thought of both as an ancient system of ‘scientific knowledge’ or a ‘divine science’; only its main aim is not so much to explore and explain the outer world, but primarily how the inner world of each individual is ruled and held together. This understanding too shall give the student certain powers, but rather over the forces of his own inner nature.
This system then, is a system, which can give a diligent student a higher than human, that is, in fact, a divine perspective. Hence we could even called it a divination system if the latter term would not have acquired such a distorted meaning in modern times.
In Buddhist countries it often is used as a system for initiation, as a system for developing higher faculties and as a system for understanding the world, both without and within.
Consequently, the aim and use of this system is principally quite different from what you find in common religion. The primary aim of most common religions is, first to see to it, that each member of society reaches a good standard of ethical development. The main agenda of the study of this system on the other hand, is the development of the mind and the will, and the exploration of the inner workings of things. And thus, like all genuine education, it is also a means for making knowledge oneself.
Of course you may gain knowledge from reading just any book, but not all books enable you to make knowledge yourself. And unless you know how to make knowledge yourself, you will always depend on outside sources for keeping you going. On the other hand side, if you know how to make knowledge yourself, you may become both independent yourself, while also becoming for others a wellspring whence solutions for the problems of life shall flow forth. You may compare this with either giving a person a bag of rice, which may feed a man and perhaps his family for a few weeks, but which when it is finished up, will leave that man in the same situation as before; that is, hungry and helpless. Or, in contrast, educating a man as to how to clear land, how to plant seeds, how to harvest crops, etc. An education which of course may take a considerable amount of time, and which will be only of use, if it thereafter is put into practice. But which once acquired, can lead to a much greater amount of independence and the acquisition of yet higher things than that.
Thus, there are definite benefits to be gained. Nevertheless, we also must state, that when studying an old system such as the Abhidhamma, a modern student has to have some tolerance. Because, being such an old system, it naturally may appear not quite perfect, in that, it may contain various types of information that seem to contradict what is now generally accepted. This should not prevent the modern student from such study, because the main purpose of ancient systems never was to provide accurate details about the world, but to give to those who were inclined to its study, a map of the inner side of life, the details of which had to be worked out by each student for himself. And that may be the most important point, that a modern student will appreciate about such a system, that is, the method of a “closed system”, with a limited amount of concepts that can yet be used, if used wisely and with keen intuition, to unriddle the whole mystery of life.
Actually without studying any such system, without any training on a path of learning, a person has little reason to pay attention to life or to remember or process his life experiences. He will always be too busy with “life-stuff”. On the other hand, possessing a training and studying a system, a person has reason to pay attention to and remember even the unpleasant experiences of life. Many-one might be regularly surprised by ever the same unfortunate happening, ever lamenting or being angry. With this system, he will have a method to work on his life. That is, the Abhidhamma system can give the framework into which a person can fit his life experiences and understanding, both of the nature of personal insights, as well as from reading scriptures. If then thus everything is put into its rightful place within the system (de-filement means putting things into the wrong place, wrongly filing things), every situation may be mastered in a way that leads to further understanding and wisdom. And by that to infinitely more potential for constructive action.
A modern student of course should also study it, at least to some degree in conjunction with the perhaps often more accurate knowledge (as far as its subjects go) of modern science. And actually if this is done properly, the result will be much more lucid in either of the two disciplines. That is, the ancient system will first of all show the outline and unity of a closed system, thereby giving a certain superstructure into which all other acquired knowledge can be fitted. And then, it will also provide knowledge that modern science still is vastly ignorant of, such as the law of kamma and the existence of various planes of existence. While on the other hand, the modern knowledge can fill out various gaps and increase the quality of the details.
Still, it should be needless to say, that the aim of a meditator or truth seeker, which are the main types of persons who would study the Abhidhamma, is not to just acquire more and more random knowledge, but rather proficiency in a path that becomes only discernible with the intelligent study of life. Thus, the outer end is of course not intellectual or mental, but what is aimed at is the highest spiritual reality. But the main instrument for reaching that end is the instrument of mind. That will be the initiator for the will and devotion, seeing to it that no step, or at least no important step, is taken blindly.