General Observations of Animals

Some animals crawl, march, run, or jump, while others fly, raising themselves in the air and travelling through different spaces.

Others, living in the depths of the waters, swim and transport themselves to different areas in the expanse of the surroundings waters.

The animals are not, like the plants, in a situation where they find within range right next to them the material on which they feed.

Among animals, even those which live by seizing prey must go seek it out, follow it, and finally seize it. Thus, they must have a faculty of motion and even of moving around so as to be able to obtain the nourishment which they require.

Moreover, those animals which multiply by sexual reproduction do not offer sufficiently perfect hermaphrodites to enable them to meet their needs.

Thus, it is again necessary that they can move around to put themselves in a situation where they can reproduce.

For those animals which, like the oysters, cannot change their positions, the environmental surroundings must provide means for such movement.

Thus, these needs have the capacity to provide the faculty which the animals possess of moving parts of their bodies and of carrying out movements advantageous to their own conservation and that of their race.

In Part 2, we will look into the source of this astonishing faculty, as well as the cause of the most remarkable which we find among them.

With regards to animals:

1. Some do not move or move their parts only as a consequence of their stimulated irritability.

But they do not experience any feeling and cannot have any sort of will power. These are the most imperfect animals.

2. Others, apart from movements which their parts can undergo through their stimulated irritability, are susceptible to experiencing sensations and possess an intimate and very obscure feeling of their existence.

But they act only through an interior impulse by a tendency which draws them to some object or other, so that their will power is always dependent and led on.

3. Still other animals not only experience movements in some parts as a result of their stimulated irritabilty, are susceptible to receiving sensations, and enjoy an inner feeling of their existence,

In addition, they have the ability to form ideas for themselves, although confused, and to act by a determining will power, which is nevertheless subject to tendencies which carry them, once again, exclusively towards certain particular objects.

4. Some other animals, the most perfect, possess to a high degree all the abilities of the preceding ones and enjoy, in addition, the power of forming for themselves clear or precise ideas of objects which have affected their sense and drawn their attention, of comparing and combining these ideas up to a certain point, and deriving from them judgments and complex ideas.

They have:

• the ability to think
• a less captive will power

These permit them to vary their actions.

In the least perfect animals, life is without energetic movements.

• Irritability alone is enough for vital movements.

But vital energy increases in proportion to the complexity of organic structures.

• This creates a limit where in order to provide sufficiently for the activities essential to vital movements, nature had to add to its means.

This is why nature used muscular action to establish a system of circulation.

• This caused the acceleration of the motions of fluids.

This acceleration itself later grew in proportion to the muscular power which it required.

No muscular activity can take place without the action of nerves.

• And so nerves were everywhere necessary to accelerate fluids.

In this way, nature added muscular action and neural influence to the insufficient irritability.

But this neural influence which gives rise to muscular action never brings it about by the path of feeling, something I hope to demonstrate in the second part.

Later I will establish there that feeling is not at all necessary for the carrying out of vital movements, even in the most perfect animals.

Thus, existing animals are clearly distinguished from each other by:

• the features of their external shape
• the consistency of their bodies
• their size, and so on
• their faculties

The most imperfect organism are reduced, in this respect, to the most limited state.

not having any faculties other than those appropriate for life, not moving except through a power outside themselves; whereas, the others have progressively more numerous and more eminent faculties, to the point where the most perfect display a collection of faculties exciting our admiration.

Each acquired faculty is the result of a special organ, or system of organs, which gives rise to it.

The most imperfect animal has no organ whatsoever.

• Consequently, it has no other faculty than those which belong to life itself.

The most perfect animal has the most faculties.

The organic structure gradually gets more complex.

• All the organs, even the most important, arise one after the other through the animal ladder.
• These organs successively perfect themselves by the modification they go through

The most important ideas in the study of animals are:

• the internal organic structure of animals
• the different systems throughout the animal ladder
• the various specialized organs

If animals are astonishing for their faculty of movement, then many of them are considerably more astonishing for their faculty of feeling.

But this faculty of movement is very limited in the most imperfect animals where it:

• is not voluntary
• only occurs through external stimuli, so it improves later more and more.
• succeeds in originating within the animal itself
• finishes by being subject to the animal’s willpower.

Similarly, the faculty of feeling is also very obscure and limited in the animals where it begins to occur.

It develops progressively later until it shows as intelligence.

In fact, the most perfect animals have simple and even complex ideas, passions, memory, a source of dreams.

They experience involuntary returns of their ideas, even their thoughts, and are up to a certain point capable of instruction.

The greatest achievement of the power of nature and proof that a long time has been taken up is in nature succeeding in giving a living body the ability to:

• move itself
• perceive objects beyond itself
• form ideas for itself, by comparing the impressions which it has recieved from them with those which it was able to receive from other objects
• compare or combine these ideas
• produce judgments which are for it ideas of another order
• think