1. In the two orders of things- those whose existence is that of process and those in whom it is Authentic Being- there is a variety of possible relation to Cause.
Cause might conceivably underly all the entities in both orders or none in either. It might underly some, only, in each order, the others being causeless. It might, again, underly the Realm of Process universally while in the Realm of Authentic Existence some things were caused, others not, or all were causeless. Conceivably, on the other hand, the Authentic Existents are all caused while in the Realm of Process some things are caused and others not, or all are causeless.
Now, to begin with the Eternal Existents:
The Firsts among these, by the fact that they are Firsts, cannot be referred to outside Causes; but all such as depend upon those Firsts may be admitted to derive their Being from them.
And in all cases the Act may be referred to the Essence [as its cause], for their Essence consists, precisely, in giving forth an appropriate Act.
As for Things of Process- or for Eternal Existents whose Act is not eternally invariable- we must hold that these are due to Cause; Causelessness is quite inadmissible; we can make no place here for unwarranted "slantings," for sudden movement of bodies apart from any initiating power, for precipitate spurts in a soul with nothing to drive it into the new course of action. Such causelessness would bind the Soul under an even sterner compulsion, no longer master of itself, but at the mercy of movements apart from will and cause. Something willed- within itself or without- something desired, must lead it to action; without motive it can have no motion.
On the assumption that all happens by Cause, it is easy to discover the nearest determinants of any particular act or state and to trace it plainly to them.
The cause of a visit to the centre of affairs will be that one thinks it necessary to see some person or to receive a debt, or, in a word, that one has some definite motive or impulse confirmed by a judgement of expediency. Sometimes a condition may be referred to the arts, the recovery of health for instance to medical science and the doctor. Wealth has for its cause the discovery of a treasure or the receipt of a gift, or the earning of money by manual or intellectual labour. The child is traced to the father as its Cause and perhaps to a chain of favourable outside circumstances such as a particular diet or, more immediately, a special organic aptitude or a wife apt to childbirth.
And the general cause of all is Nature.