Chapter 8

The quantity of excitation needed
for the fundamental feeling in each animal

1864. The vital forces, therefore, are more powerful than the physical and chemical forces which they are destined to dominate. This is indeed how things must be if it is true that vital forces are those proper to a feeling individuated in a suitable organism. Physical and chemical forces, on the other hand, are instinctive forces of feelings which lack an organism and are connected to atoms or molecules devoid of unity. Feeling and its consequent instinct must certainly be less vigorous in unorganated than in well-organated bodies. The following question now arises: 'How can the quantity of force of animal instinct be determined?' This question embraces several others. We begin, therefore, by restricting it to the fundamental feeling of excitation.

Why in a given organisation does excitation naturally maintain a certain measure and maximum quantity? The activity of the vivifying act, as we said,(27) seems inexhaustible. What is the law, therefore, which limits and determines the quantity of excitation in the fundamental feeling of a given animal. For example, if the reciprocal action of lungs, heart and brain originates from animal activity, why is this action not greater? Why does circulation not increase in speed?

1865. The fundamental feeling originates from the extended felt element and from excitation. Let us see how excitation arises. Feeling diffused in extension is the work of the life instinct. But excitation supposes a prior stimulus provided by nature. When this stimulus is applied to an opportune organisation, it arouses sensation which is still the work of the life instinct because it is only a modification of the feeling which this instinct has produced.(28)

This first sensation moves the sensuous instinct, which continues the movement begun by the sensiferous stimulus. This movement, now circular, perpetuates the excitation of the fundamental feeling. Our question, therefore, is reduced to this: 'Why does the sensuous instinct work with a certain degree of activity which limits and determines the quantity of excitation proper to the fundamental feeling of a given living being?'

1866. The law determining the degree of activity of the sensuous instinct(29) takes the following form when applied to our question: 'The sensuous instinct operates with a quantity of action proportioned to the feeling from which it moves, and continued until it becomes pleasurable.'

1867. From this law it follows that the activity of the sensuous instinct is limited:
1. by the quantity of feeling and hence of the primitive stimulus which has aroused the feeling;
2. by the pleasure that the animal experiences in the action of instinct.

1868. But what determines the pleasure that the animal finds in the action of instinct? The sole determining factor is the level of mobility in the organisation which is more or less suitable for producing new stimuli and new sense-experiences serving to place the sensuous instinct in activity once more. The sensuous instinct can move only a living body, that is, a living organism. This is an absolute limitation proper to the instinct. If the sensuous instinct experiences resistance in a body, it will cease to act as soon as the effort it makes is more troublesome than the pleasure connected with its action.

1869. Experience shows that this instinct always finds some resistance, even in its choice of the easiest motions. Hence, for its action not to cease, the instinct, before it ends its operation, before the operation ceases to be pleasurable, should with its action put into being other stimuli to regenerate its own activity. If the stimuli reproduced are less efficacious than preceding stimuli, the activity of the sensuous principle gradually decreases. If this diminution is continuous, the instinct reaches perfect quiet, with which animal life spontaneously ends.

1870. The phenomenon of pain, which belongs to life instinct, may arise as a result of some defect of organisation or through some alteration in the mixed organic being. In this case, the sensuous instinct receives from pain a new, opposite activity, that is, tending to diminish or remove pain rather than continue and increase pleasure. This activity follows the same laws of activity produced by pleasure and is, therefore, as great as the pain, and necessarily sufficient to diminish or at least not increase the pain. If the movements produced by this activity no longer reduce but increase the pain, the sensuous activity would cease from that moment. The quiet following on abandonment to pain would be present, and the animal would fall into lethargy and discouragement. At this point, the medicinal forces of nature come to a close and give way to disruptive forces which easily destroy the organism and cause death.

Notes

(27) AMS, 377-379.

(28) AMS, 392-400.

(29) AMS, 443-457.