We are in this world. We can sense the world through our five senses. This is fact and not of anyone opinion. We have been in this world since we were born. And we will still be living in this world as long as our chance allows us to live. And we will definitely be leaving this world no doubt.
The whole matter is clear and there is nothing to argue on this proposition. As we have been living, there were many many people who had lived in this world on this earth. When they were living they were striving for__ their lives and their continuing existence. Some merely did for their sake. But some left invaluable facts through their experience and their wisdom.
There have been many many branches of science and arts that study their respective subject matters. Along with the advancement of technology there have been many recorded materials on each of selective subject. Some subjects are still going advanced and research is being performed on each subject matter. These subjects seem to be endless.
But whatever these subjects are leading and behaving, everything will fall into one of the four dhamma unltimately. Any given fact_ will be one of these four dhamma or four ultimate realities. These four ultimate realities are also known as paramattha dhamma or paramattha sacca or ultimate truth or universal truth. Because these four dhamma or these four nature are always true at any given time and at any place and in any era.
There are complex relations between these four ultimate realities. These relations can be studied in the Buddha Abhidhamma and the most complex and highly respectable dhamma among The Buddha Abhidhamma is patthana. To understand_ patthana, four ultimate realities or paramattha dhamma should first be understood in detail.
Before going into some detail, it will be a good idea to have a bird eye view on these four paramattha dhamma. Everything that we can see, we can hear, we can smell, we can taste, we can sense through our body and we can reason out through our working mind will fall into four categories.
These four categories are 1. citta or consciousness or state of mind or state of consciousness or awareness, 2. cetasika or mental factor or mind conditioner, 3. rupa or matter or material or non conscious nature, and 4. nibbana or absolute peace or total extinguishment of all fire including lobha or craving, dosa or hatred or aversion, and moha or ignorance or delusion. To remeber easily and to be simple, there are only these four things in the whole universe. They are citta, cetasika, rupa, and nibbana. There is nothing more than these four dhamma in terms of ultimate sense.