Sense of Smell

Smell is the third of the senses through which the human person is introduced into another world of ideas, from which he becomes enriched through all kinds of knowledge. The soul through the sense of smell perceives the invisible world of odors and discovers the hidden treasure of perfume poured out; smell is the third sense, and has its seat in the olfactory nerve. Through smell the soul distinguishes odoriferous bodies into pleasant and unpleasant, into fragrant and malodorous, and accepts what is delightful and rejects what is unpleasant. Although smell appears to provide an addition, generously distributing and enriching those of the ether, serving the function of nourishing the human person, it was not created solely for this purpose; from the services it provides to the soul for enrichment from various kinds of knowledge, one can regard it more as an organ functioning for the spirit appointed to complete the knowledge of the human person than as something material appointed for the service of the body; the spiritual character of smell is testified to from two things: on the one hand from its small use in the selection of foods, on the other from its great

Use in the discovery of pleasant and fragrant objects; through smell we receive pleasures or aversions. Hence smell is referred to the soul, for it judges the quality of the odor. The human person through smell receives pleasures which have nothing in common with the body; the function of distinguishing pure from polluted air is indeed a function referred to life, but no less to the soul, for it gives notions. The function of smell was appointed to inform the human person about what happens around him and does not fall upon any of his other senses.

The spiritual character of smell is testified to by the structure of the nose, which, existing in harmony and communion with the organs of taste and hearing, declares its destination to serve the needs of the soul; what grace would a superbly harmonized song have if the ear had a structure similar to that of animals? It would lose all its melody and would stir no sensation of pleasure in the soul, and the human person would lose the idea of melody and harmony and would remain incomplete. How much grace does it not give to the face of one whose proportions it regulates and makes so beautiful as to present the idea of beauty portrayed before our eyes! Smell and the two preceding senses have such a relation to the soul that one can argue that they were created more for the soul than for the body; for their perfection and the structure of their organs have a higher purpose than what appears; they were appointed to serve more the soul than the body.

Such is the sense of smell in the human person; let us now turn to the sense of smell in the animal and see what it is like.

And animals, like the human person, have the sense of smell; some of them indeed have this faculty more acute than the human person.

The dog discovers the tracks of his own master in the forest, and the tracks of the hare and other animals and birds; the wild goat senses from afar the hunter who is many leagues away and his other enemies; this is observed in many other animals as well; tracker dogs have the keenest sense of smell. Birds, especially carnivorous ones, have equally keen sense of smell; from distances of many miles they smell from afar their own peculiar food; the proverb “where the corpse is, there the eagles” reveals the enormous sense of smell of these birds. The serpent apparently has acute sense of smell, for it can find the corpse of its dead mate by traveling long distances, if the body has been dragged into the ground. The power of smell appears also in insects; well-known is the sense of smell of common and flesh-eating flies, which from distant distances perceive the distinctive odor of each; very keen sense of smell have beetles and bees and wasps and most other insects, which from smell distinguish many kinds and types of fruit and leaves designated for them as food. The ant from the depth of its labyrinth receives through smell the sensation of the odor rising from the top of the flowering fig, and climbs upon the branches of the fig tree in order to approach the hole of the odoriferous green fig. Fish also appear to have sense of smell, some indeed a strong one, for they smell the substances scattered upon the sea by fishermen from distant distances. Strong sense of smell is not lacking even in invertebrates, mollusks, arthropods, and radiate animals, which although appear to be deprived of a specific distinct sensory organ of their own; in some of these it appears from observations that they have a very developed sense of smell; but let us examine whether the sense of smell in animals also has this spiritual character of it.

From the observations made it appears that the sense of smell in animals is entirely material and a necessary organ for the nourishment of animals and their preservation; for through smell they discover foods; through smell they distinguish them; through smell they avoid enemies; through smell they recognize what tends to the perpetuation of their species and in general through smell they are preserved, develop, and continue. From the peculiar acuteness of the sense of smell in different animals toward specific odors appears its particular purpose, and from the characteristic indifference toward all other fragrant or malodorous substances appears the material purpose of the sense. By way of example, the dog, while discovering the tracks of its prey and the tracks of its master through its fine sense of smell, finds no pleasure or fragrance in the most fragrant flowers; it passes through fragrant meadows, whose fragrance floods the air, and yet no impression is created in it; fragrance and malodor do not create even a single impression; it has specific and particular sense of smell, proportionate to its instinct; such as the instinct, such also is the sense of smell; the sense of smell can be regarded as the sensory organ of instinct; why does the flesh-eating fly perceive the odor of meat? So that it may perpetuate its species. Why are the eggs of different insects deposited on the same ground, because the sense of smell, guided by instinct, distinguishes them? Does not the ant climb to the top of the fig in order to breathe the fragrance more closely? Not at all, but to grasp its larva emerging from the hole of the fig; instinct guides the sense of smell. That the sense of smell in the animal is entirely material and instinctive is demonstrated by observation of animals in general. The nostrils of fish communicate not with the brain, but with the pharynx, for what else did they need than food? Many animals, birds, and insects act with such an impulse and so very quickly from the impelling odor that not the slightest suspicion remains that they do not proceed with judgment; the specificity toward certain odors and just as the inadequacy toward others is proof of the entirely material function of this sense.

From the entire investigation we draw the positive conclusion that the sense of smell in animals is an organ of the animal’s instinct, is a material sense, that it has no relation to the spirit, that it is imperfect and particular. How different is the sense of smell of the human person! What perfection and what harmony unite it with the soul! What is its purpose! How graciously its organ was situated! The difference of the sense of smell between the human person and the animal is such and so great as is that which distinguishes the circumference of the human person and his particular purpose.

Let us now proceed to the investigation of the sense of hearing.