What really distinguishes plants and animals?


Animals have brains.


Oh yes, when I mentioned recent studies in the OP, I definitely was referring to ancient history…

If you really want to know why I chose to discuss this topic specifically, I simply wanted to get a better understanding of the tripartite nature of the soul. Or is contemplating on the souls of things useless Greek stuff?


FROM Father John A. Hardon’s Catholic Dictionary:

SOUL. The spiritual immortal part in human beings that animates their body. Though a substance in itself, the soul is naturally ordained toward a body; separated, it is an “incomplete” substance. The soul has no parts, it is therefore simple, but it is not without accidents. The faculties are its proper accidents. Every experience adds to its accidental form. It is individually created for each person by God and infused into the body at the time of human insemination. It is moreover created in respect to the body it will inform, so that the substance of bodily features and of mental characteristics insofar as they depend on organic functions is safeguarded. As a simple and spiritual substance, the soul cannot die. Yet it is not the total human nature, since a human person is composed of body animated by the soul. In philosophy, animals and plants are also said to have souls, which operate as sensitive and vegetative principles of life. Unlike the human spirit, these souls are perishable. The rational soul contains all the powers of the two other souls and is the origin of the sensitive and vegetative functions in the human being

In all of the Universe & the Worlds Creation; ONLY humanity has a rational {Gen 2: 6-7} and immortal Soul

The answer to your question is the degree of complexity of each living things soul.


This is why I was asking. What exactly distinguishes the plant soul and animal soul?


I will read that later. Thanks.


frankly; not much;

father pacwa has said that plants & animals have “mortal souls”

humans have “immortal souls”


A Plant’s Soul depends totally on Nature {passive}

An animals souls is instinctive which makes it more complex {passive-aggressive}

BOTH are mortal



All souls are produced by earthly processes except for human souls.


I appreciate the fact that there is a grey area, but if i say that i am a plant, then is not the case that i am being delusional. Surely there must be some genuine distinction between me and a plant?


father pacwa said that both plants & animals have souls; neither of which are immortal

should God choose that your favourite carrot, marigold, poodle or yellow fin tuna be in heaven with us

May His will be done…


My view entirely. There seems to be an almost Classical and Medievalist Fetishism in some circles, as if if Aristotle or Aquinas said it, we can just merrily ignore the last five hundred years of science. I’m not saying everything the Classical and Medieval philosophers wrote was wrong, and certainly their work informs a lot of what science became in the Enlightenment. But honestly, when it comes to topics like biology and cosmology, trying to force fit the musings of people who lived a thousand years or more before modern disciplines like cosmology and biology even existed seems rather strange.

Other than as a interesting historical aside, what does it matter how Aristotle classified things? Linnaeus would be the starting point in my view for any taxonomic questions, and really even a lot of what Linnaeus and his heirs dreamed up has had to be shifted as molecular data draws new lines between different branches on the tree of life.

I have a great deal of respect for men like Aquinas. They did the best they could with the extent of the knowledge at the time, but the simple fact is that they didn’t have the resources or the body of knowledge that we have today, so any respect has to be tempered with the simple fact that we know more than they did.


Animals possess the combination of common sense, imagination, the estimative faculty, and sensitive memory. With these faculties, animals can adapt behavior in the present based on their experiences in the past.


Some members of Animalia don’t even have a central nervous system (think jelly fish), and most certainly the earliest members of that kingdom didn’t have any kind of specialized nervous system at all. Even with motility, well plenty of plants and fungi have motile stages. If you go by the way they produce energy, well, yes most plants create their own energy, but then again, if you look at the opposite side, fungi gain energy pretty much like animals, to the point that these days fungi and animals are considered sister clades, and are grouped together under the opisthokonts.

As with all things in taxonomy, the definitions don’t quite cover all the cases. It’s why taxonomy has been steadily shifting towards including more molecular data, and not merely morphological data. Genetic lineages are a lot more reliable, because of the extent of variability even in related groups.

It really is at the point that if an organism has a cell wall, it’s not an animal (and then you have to analyze what the cell wall is made of to determine whether it’s a plant, a fungi, or the various “protists”), otherwise it’s an animal (but again, nature doesn’t play by nice taxonomic rules, so expect strange outliers).


Philosophy leaves, as it should, the determination of the material composition of beings and the categorization of groups based on the same to the scientific community.

The immaterial properties of animals are in the domain of philosophy. If and when science links these internal senses as emanating solely from specific organs or body parts then philosopher will examine the data and, if necessary, modify its findings. I believe science is doing that work now.


The vegetative soul accounts for the functions of nutrition and reproduction. The sensitive soul, is that by which higher animals perceive and respond to their environment and includes the power of local motion.

In recent Taxonomy we have these Kingdoms:

  • Bacteria
  • Archaea
  • Protozoa
  • Chromista
  • Plantae
  • Fungi
  • Animalia


is this a homework question


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