Epistemology and the Eucharist

I’m interested in what some philosophers (especially Catholic philosophers) have said about the Eucharist, such as: how do we know that the Body and Blood of Jesus is truly present in the Eucharist and if we can really know and if its even important for us to know. I don’t know any direct works about the subject, and I would really like to debate with my non-Catholic philosopher friends. And I suppose that this subject is unlike any other epistemological topic, so who can I read or do any of you have some ideas? I’m also looking for philosophic and not theological works.

Off the top of my head, I can’t recall any specific quotes by philosophers on the subject, although with regard to whether it’s important for us to know that the Eucharist is really Jesus, Saint Paul remarks…

“For he that eateth and drinketh unworthily, eateth and drinketh judgment to himself, not discerning the body of the Lord.
1 Corinthians 11:29

Mostly, Catholic philosophers seem to have seen recognition of the Real Presence as a basic tenet of the faith, taken as a result of the only possible reading of John Chapter 6, and devoted more of their energy to explaining -how- it was possible, but I might be mistaken about that.

There’s always Aquinas online: Transubstantiation

A Key to the Doctrine of the Eucharist by Vonier is another good resource.

Neither philosophically, scientifically, experimentally, or any other way devised by humans can it be proved that the Church’s doctrine of transubstantiation is true. It is simply a matter of faith and rests solely on the words of Christ. At the last supper, when Jesus took bread and said “this is my body” and taking the chalice said “this is my blood” catholics believe that what Jesus said is true since He is the Truth. Jesus, by divine power and suspending the laws of nature, changes the bread into his body and the wine into his blood. We do not presume that we can place limits on God’s almighty power or that He cannot do things which our little minds cannot understand.

St Thomas Aquinas wrote a brillant treatise on the Church’s doctrine of transubstantiation. In this treatise, Aquinas does not try to prove scientifically the miracle of the Eucharist, that is impossible. Rather, he explains what takes place during the miracle of the Eucharist in so far as man’s mind is capable of understanding something of it.

I should also add that transubstantiation cannot be proven to be false by any means.

This is worth reading, although Anscombe is not trying to prove that transubstantiation occurs, since like Richca says, it is a miracle beyond our understanding.

It’s a staple of Catholic philosophy that all knowledge begins in the senses. And that’s true of just about everything else–except the Eucharist.

Because in the Eucharist, sense perceptions remain while substance changes. That means that sense knowledge is of no use to us there. The consecrated species can in no way be differentiated from the unconsecrated species except by our knowledge of its consecration.

Here’s a philosophical approach (a nominalist one).

  • Something ‘is’ what we call it. e.g. person A is only “Peter” because we call him “Peter.” Judged as a thing in itself, he could be called, as so ‘be’, anyone. A horse is only a horse, because we call it a “horse”. It might be called something else. But it is a horse because we, by convention, call it a “horse”. To someone who speaks only Latin, it is not a ‘horse’ but an ‘equus’
  • Similarly, the priest calls the substance X, “The body and blood of Christ”. The relevant interpretive community (those who believe) assent to this the application of this designation.
  • Therefore it IS “The body and blood of Christ.”

This seems unorthodox, but, in fact, the same sentiment is found in various Medieval writers.

Here is a very rough and quick idea I’ve thought of (be forewarned that I’ve been reading Leibniz the last few days):

My empirical observations tell me that a piece of bread can not instantly change it’s material and essential characteristics. However, it could be the case that the proposition that it is the Body and Blood of Christ is true. Perhaps my senses are not deceptive but instead my ability to reason based on my sensory observations is flawed.


  1. Transubstantiation is a miracle of God, but although abnormal to us, such miracles are not against nature because nature stems from God.
  2. All of our empirical knowledge could be wrong because of this inability to deduce the truth of propositions whose truth or falsity have depended on a posteriori knowledge, and we are thus not able to determine whether or not the Eucharist is really the Body and the Blood by our senses at all. And all possible knowledge is a priori.
  3. As a result of (2), it is not against reason to assert that substantiation truly is a miracle, but is instead above reason and belief is not unjustified.
DISCLAIMER: The views and opinions expressed in these forums do not necessarily reflect those of Catholic Answers. For official apologetics resources please visit www.catholic.com.