A little more than 100 years ago, the science of physics discovered that all material objects did not actually exist by themselves, but consisted of atoms. Over the following decades, physicists gradually learned that atoms did not exist by themselves either, but consisted of rapidly fluctuating subatomic entities that emerged from the unknown, only to almost instantly disappear again. These discoveries were made by colliding atoms and subatomic entities with each other and analyzing the traces left behind. The laboratory experiments went hand in hand with extensive mathematical calculations that formed the basis of quantum field theory, according to which there is no such thing as stable elementary particles – rather, it is a question of small vibrating packets of not understood basic energy forms.
More than 2000 years earlier, Buddhist monks and scholars discovered and analyzed similar phenomena and came to very similar conclusions. However, while the physicists deal only with the material parts of the universe and neglect the existence of mind and consciousness, these phenomena were the primary focus of the Buddhist monks and scholars. Their discoveries and conclusions were formulated in the Abhidhamma – a prominent part of the canonical Buddhist literature – of which the Patthana is the seventh and final book.
All things are ultimately nothing but manifestations of citta, cetasika, rupa and nibbana. Citta, cetasika and rupa dhammas are conditioned by other things. Nibbana on the other hand is not conditioned by anything.
Citta is consciousness. It is the nature which is capable of knowing, sensing or being aware of objects: the seeing mind, the hearing mind, the smelling mind, the tasting mind, the tactile-feeling mind, the thinking mind are examples of citta. Cetasika always arises with citta and disappears with citta. Examples of cetasikas are irritation, anger, hatred, rage, jealousy, craving, ignorance, depression, fearlessness, shamelessness, love, attachment, clinging, conceit and many more. Rupa is material, all matter — solids, liquids, gases, molecules, atoms, quarks, leptons, etc. is made up of rupa dhammas. Nibbana is the ultimate reality.
According to Patthana, there are (usually) 89 different citta dhammas, 52 cetasika dhammas, 28 rupa dhammas and 1 nibbana dhamma. In certain advanced meditative states, 32 more citta dhammas may appear.
On this site, all of these dhammas and their interactions will be described in more detail