585. What do you think of the division of the natural world into three reigns, the mineral, vegetable, and animal, to which some naturalists add a fourth class – viz., the human species; or that other division of the world into two classes – viz., the organic and the inorganic? Which of these divisions is to be preferred?
"They are all good; as to which is best, that depends on your point of view. From the point of view of matter, there are only inorganic and organic beings; from the moral point of view, there are evidently four degrees."
These four degrees are, in fact, distinguished by well-marked characteristics, although their extremes seem to blend into each other. Inert matter, which constitutes the mineral reign, possesses only mechanical force; plants, composed of inert matter, are endowed with vitality; animals, composed of inert matter, and endowed with vitality, have also a sort of instinctive intelligence, limited in its scope, but giving them the consciousness of their existence and of their individuality; man, possessing all that is found in plants and animals, is raised above all the other classes by a special intelligence, without fixed limits, which gives him the consciousness of his future, the perception of extramaterial things, and the knowledge of God.
586. Are plants conscious of their existence?
"No; they do not think; they have only organic life."
587. Do plants feel sensations? Do they suffer when they are mutilated?
"Plants receive the physical impressions which act upon matter, but they have no perceptions; consequently they do not feel pain."
588. Is the force which attracts plants towards each other independent of their will?
"Yes; for they do not think. It is a mechanical force of matter that acts upon matter; they could not resist it."
589. Some plants, as, for instance, the mimosa and the dionea, have movements which give evidence of their possessing great sensitiveness, and, in some cases, a sort of will, as in the case of the latter, whose lobes seize the fly that lights on it, in order to suck its juices, and even seem to set a snare for it, in order to kill it. Are these plants endowed with the faculty of thought? Have they a will, and do they form in intermediate class between the vegetable and animal natures? Are they points of transition from the one to the other?
"Everything in nature is transition, from the very fact that everything is different, and that everything, nevertheless, is linked together. Plants do not think, and have consequently no will. The oyster that opens its shell, and all the zoophytes, do not think; they have only a blind natural instinct."
The human organism furnishes us with examples of similar movements that take place without any participation of the will, as in the organs of digestion and circulation; the pylorus closes itself at the contact of certain substances, as though to refuse them passage. It must be the same with the sensitive plant, the movements of which do not necessarily imply perception, and, still less, will.
590. Is there not, in plants, an instinct of self-preservation which leads them to seek what may be useful to them, and to avoid what would do them harm?
"You may call it, if you will, a sort of instinct: that depends on the extension you give to the word; but it is purely mechanical. When, in chemical operations, you see two bodies unite together, it is because they suit one another, that is to say, there is an affinity between them; but you do not call that instinct."
591. In worlds of higher degree, are the plants, like the other beings, of a more perfect nature?
"Everything in those worlds is more perfect; but the plants are always plants, as the animals are always animals, and as the men are always men.