The awareness of the observer depends on the position of the percipient event in this systematic correlation.

I will use the term 'ingression into nature' for this systematic correlation of the blue with nature.

Thus the ingression of blue into any definite event is a part statement of the fact of the ingression of blue into nature.
In respect to the ingression of blue into nature events may be roughly put into four classes which overlap and are not very clearly separated.
These classes are (i) the percipient events, (ii) the situations, (iii) the active conditioning events, (iv) the passive conditioning events.

To understand this classification of events in the general fact of the ingression of blue into nature, let us confine attention to one situation for one percipient event and to the consequent _roles_ of the conditioning events for the ingression as thus limited.

The percipient event is the relevant bodily state of the observer.