Here he should know the theoretical aspect of mind and matter which constitute the so-called being or man.
A being whom we call 'man' is indeed composed of mind and matter only. According to Buddhism apart from mind and matter (nama rupa )' which constitute the so-called man, there is no such thing as an immortal soul (Atta), which lives (behind them) inside him.
Our body is composed of particles of matter (rupa). Matter, in fact, is the visible complex of invisible qualities and forces known in Pali as Mahabhuta, essential or great elements, Along with the arising of these four primary elements there also arise four secondary characteristics of matter, i.e. colour, smell, taste and nutritional quality. The whole physical body, composed primarily of these material qualities, can be experienced only in terms of these eight elemental properties of matter.
In fact, these eight properties are inseparable and interrelated, yet different in cosmic nature with one another.