Transubstantiation and the essence of "essence"

I am in possession of Edward Feser’s book with an introduction to the thought of Saint Thomas Aquinas and have attempted to read it twice already, but I never made it quite through. In fact, I only got through the first two or three dozen pages until I was either confused or forgot to continue and thus lost the connection.

Anyway, I remember that Saint Thomas makes a distinction that the Church uses to explain Transubstantiation between the essence and the accidents of a given thing. An example used is that of a plastic ball, the essence being its “ballness” and the accidents being things like colour, hardness, etc. Applied to the Blessed Sacrament, the essence is “bread” before the Consecration and “Christ” afterwards, while the accidents remain: taste of bread, smell of bread, structure and chemical composition of bread. At least that’s how I understand it and would phrase it.

Now, I struggle to understand the distinction of essence and accidents in general. I know what Saint Thomas means by them, I think, but somehow it seems foreign. Thinking about it for a bit, I came up with this question to express my understanding of it. Obviously, it is anything but a philosophical treatise, but I feel it expresses my struggle well.

The question is this: Isn’t the essence of a thing basically the sum of all its accidents?

Perhaps I have failed to completely understand Saint Thomas’ approach, who knows! Maybe a Thomist here could help me. :slight_smile: Thanks!

No, essence isn’t the sum of the accidents. If that were the case, then a change of substance would be a change accidents and vice versa. A black man would have a different essence than a white man, and consequently they would be different races or species. The essence is what an object is in itself. The essence of a man is what distinguishes him from everything else, and unites all men. A man is a rational soul united to a material body.

Far from a thomist, but here’s my overly-simplified take on it.

I have a keyboard. The accidents - the sound and resistance of the keys, the reaction time, the battery life - are its physical properties. I write creatively, so in a sense, it has a creative essence - like a paint brush or a guitar.

The Body of Christ has the essence of Christ because it IS Christ’s body, even if the accidents (texture taste etc) are those of the bread it used to be.

The essence of a ball is like its sphereness.

Its accidents: weight, color, material, location, age, etc.

A ball can be rubber, wooden, plastic, etc.

So with Eucharist, the material is also accidental.

But then we can ask, "What is the essence of bread?

True, undoubtedly. I just remembered that Saint Thomas had something to say about form and matter. Was it matter? Essence can’t exist without form, right? I might be a little more confused. :slight_smile:

Yes, then let us ask that. And when I ask that, I define bread by its accidents. It’s made of wheat and other ingredients, has a certain texture and taste. While I can add different ingredients, its breadness doesn’t change. But if I take away the wheat and replace it with, say, sand, it doesn’t become sand-bread. It becomes something strange and unpleasant.

So, to me, the essence of bread in this example depends on an ingredient, an accident. Or not?

You are right that an essence can’t exist without form (atleast in creation, I dont know if a Thomist would say God has form.) The form of a man is his soul, the matter is the body. A body without a soul isn’t a man.

Substance is whatever is a natural kind of thing and exists in its own right. Accidents exist in something else.

The substance of bread is bread (impersonal object), accidents: white, round etc.

The substance fo Eucharist is Jesus (personal presence), accidents: white, round , etc.

I’m no Aristotle, but no, essence is not the sum of accidents. As far as I can tell, a thing’s essence, or nature, defines the powers and properties that it can possess. Certain properties flow from the nature of a thing, for instance, the fact that a triangle has three sides is something that comes from its essence. Three-sidedness is an essential property of a triangle. An accident is a property that a thing possesses, but which does not flow from its essence. For instance, a particular triangle may be coloured green, but greenness is not essential to being a triangle.

According to St. Thomas essence is that which makes a thing the sort of thing it is, often used synonymously with natureN. So it would refer to the whole thing that exists, with its essential attributes and matter. For example a man is a material being in the species of animal, haveing a rational soul. I don’t think the word essence is used by Thomas in relation to the doctrine of Transubstantiation - that I remember. Though he uses the terms substance and accident.

Thomas has a treatise on Essence and Existence. You can read and study it here:


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