Chapter 20

The source of animal life

613. We can now improve and perfect the definition of animal. I have defined animal as 'an individual creature, materially sensitive and instinctive'. However, 'individual' needs clarification. What has already been said shows that the individuality of the animal consists in an all-pervading feeling governing all the feelings defused in a given felt extension. This explains the difference between living elements(309) and animals.

614. The elements have feeling alone; the constitution of an animal requires four conditions: 1. continuous feeling, 2. stimulation, 3. organisation which perpetuates stimulation, and 4. unity between organisation and stimulation resulting in a superior, dominant feeling. This feeling, greater than all others in the same continuum, dominates all the sensitive activities and thus individualises the sentient ens.

615. The question can therefore arise: 'Is there something particular in nature which provides animal stimulation and acts as principal agent in the formation, restoration and development of organisation?'

It really does seem that, for many animals (perhaps for all), something particular, oxygen, is present.
In fact, if any part of warm, red blooded animals lacks oxygen, it gives no signs of animal feeling. This shows that without this stimulator the greatest, individuating feeling no longer has sufficient activity to preserve or exercise its dominion in them.

616. It is a very ancient opinion that animal life has its seat in the blood. I understand this as meaning that oxygenated blood is the stimulant of the individuating feeling in human beings and in other organated animals that have a certain perfection.
One famous author misinterpreted Genesis when he rendered the phrase 'the blood of lives' (sanguinem animarum vestrarum)(310) as 'the blood is life'.(311) Similarly, in another place we read that the life of the flesh is in the blood (anima carnis in sanguine est),(312) but not that the blood itself is life.

617. The same opinion is claimed for Homer, from whom Empedocles and many others took it.(313) It was certainly introduced into the myths, where we read that souls of the dead could remember things of the present life only by absorbing the vapour of blood, or blood itself. This opinion must have been to some extent the origin of the victims offered to the dead. The following passage, preserved for us by Stobaeus, is from Porphyry:

Nevertheless, we see in all this that the sensitive soul is continually confused with the intellective soul.

618. In Italy, Pliny repeated the opinion that the soul is in the blood.(315) It has recently been re-stated by Rosa,(316) and, in England, more recently by Hunter,(317) who laid down this very helpful proposition: 'Organisation has nothing in common with life.'

619. Unfortunately these famous observers of nature did not see the difference between continuously stimulated life, for which suitable organisation is indispensable, and simple, quiescent life, which consisted solely in feeling. In any case, I think we can safely gather from their experiments that the stimulating principle of stimulated, animal life is in the blood.(318)

620. But this is not all. The experiments of Bichat proved that only red blood, not dark blood, has the power to stimulate human animal life. Now we know that blood becomes red through the oxygen breathed in by an animal from the atmosphere, but we still need to know whether, in the case of fish and other cold-blooded or white-blooded animals, the stimulation which posits their life in act comes from oxygen taken from water or from elsewhere.

621. The atmosphere then is, for many animals, a kind of reservoir and perennial fount of animal life. Empedocles seems to have seen this. According to Theodoret, Empedocles says 'The soul is a compound of ethereal and aerial substances', whose seat, according to Empedocles, is in the heart.(319) Why the heart? Because the blood, laden with oxygen, passes from the lungs to the heart. 'Empedocles,' Cicero writes, 'thinks that the soul is the BLOOD FLOWING INTO THE HEART.'(320) Here, oxygenated blood flowing to the heart is clearly distinguished from the blood which the heart pumps to the unoxygenated extremities. Moreover, because the decomposition of air in respiration is a kind of combustion and produces heat, Empedocles considered the soul to consist principally of fire, and maintained that minds were alert or sluggish in proportion to the heat of the blood.(321)

622. Even authors like Anaxagoras, Anaximenes, Archelaus and Diogenes of Apollonia,(322) who attributed to the soul the nature of air, seemed to have accepted or glimpsed the same thing, as did all those authors, like Parmenides, Leucippus, Democritus and Heraclitus of Ephesus, who attributed to it the nature of fire. For Heraclitus, fire contained the elementary principle, that is, the substratum of everything, the universal agent. He therefore granted that the elements were animated by this principle,(323) and it seems he identified, or united, light with fire.(324) Empedocles, I think, must have taken many of his opinions from this source, which demonstrates that philosophers who seem to hold contrary opinions can sometimes be reconciled, just as I have reconciled those who consider the soul aerial with those who consider it fire.

623. The very etymology of the words 'animal soul' [anima], 'intellective soul' [animus], 'spirit' [spiritus], etc. - they all mean aerial substance - seems to prove that those who first formulated them, formulators and common-sense itself, thought that the animal, in breathing, drew in its life-motor from the atmosphere.

624. Perhaps this opinion is among those which go back to the origin of the world. Scripture calls the soul 'breath'; the soul was infused by breath from the mouth of God.(325) Commenting on these passages, Tertullian says: 'The soul is substantially breath, but from its effect it is called spirit because it breathes.'(326) This led him to his error about the materiality of the soul, which St. Augustine later soundly refuted.(327)

625. If ancient scientists had been content to teach that the animal draws the principal stimulant of life from the atmosphere, they would not have been far from the truth. But having confused the intellective principle with animal life, they went astray at the first step.(328)

Notes

(309) Buffon's expression, 'organic molecules', is inappropriate. If the molecules are organic, that is, organated in such a way that stimulation is perpetuated (this is the only composition of molecules that merits the name 'animal organism'), they are tiny animals.

(310) Gen 9: 4 [5, Douai].

(311) De Maistre, Eclaircissement sur les Sacrifices, c. 1. He also says incorrectly: 'Blood was the principle of life, or RATHER blood was life.' On the contrary, blood is not life; life is united to blood. Again, he translates inaccurately Lev 17, 10 ss., where it says that life is in the blood, not that the blood is life.

(312) Deut 12: 23 says, 'For the blood is for the soul. And therefore thou must not eat the soul with the flesh' [Douai]. This, it seems, must be understood to mean that animals have living blood in place of the rational human soul because the stimulating virtue of animal life is united to the blood. The sentence that follows, about not eating the soul with the flesh, must evidently be understood as not eating the substance which contains the stimulant of animal life.

(313) Tertullian, De Anima, c. 5: 'Empedocles and Critias form the soul out of blood.' Cf. Sturz, §15 for other places in ancient authors who discuss Empedocles' opinion.

(314) Stobaeus, Eclog. Phys., bk. 1, c. 51. Authors who quote Empedocles sometimes say that according to him the blood is the soul, sometimes that the soul has its seat in the blood, sometimes that it originates from the blood, and sometimes that the blood is the instrument of the soul or the first living thing. The passages of ancient authors can be found in the collection carefully assembled by Sturz in his Empedocles, §14.

(315) Hist. Nat., bk. 12 [11], cc. 60 and 70.

(316) Cf. Gian. Rinaldo Carli, Opere, vol. 9.

(317) John Hunter, A Treatise on the Blood, Inflammation and Gunshot Wounds, London, 1794.

(318) Hunter, according to Recherches Anseatiques (vol. 6, p. 108), placed in the list of truths the opinion that blood is a living fluid.

(319) Theodoret, Graecarum affectionum curatio.

(320) Tuscul., 1: 9.

(321) Cf. the places mentioned in Sturz's Empedocles, pp. 446-447.

(322) Stobaeus, Eclogae Physic., bk. 1, c. 40.

(323) Aristotle, Metaph., bk. 1, c. 3, 7; De Mundo, c. 5; Simplicius, In Phys. Arist.; Clement of Alexandria, Strom, 5.

(324) Parmenides and Leucippus (speak) of fiery nature. Democritus referred to the fiery compound of things perceived by reason; they had a globular as well as a fiery form. According to Heraclitus, this became the body of the light of nature' (Stobaeus, Eclog. Phys., bk. 1, c. 40).

(325) Gen 2: 7; Is. 42: 5; 47: 16.

(326) De Anima, cc. 7-8; De Resurrect. Carnis, c. 11.

(327) Ep. 190; Liber de Haeres, 86; De Gen. ad litt., bk. 10, c. 24.

(328) St. Gregory Nazianzen refutes this error in a poem about the soul: