But I should ask this, are there any good arguments from a Christian perspective that the bread and cup are totally symbolic?
Of course. If one holds that Christ's sacrifice on the cross was once for all (Heb. 7:27) you might think that any idea of his body being offered again is abhorrent. (The Catholic answer to this, of course, is that the sacrifice of the Mass is not a distinct sacrifice, but the same one that occurred on the cross, being re-presented.) However, that's an objection to the understanding of the Eucharist as a sacrifice, not to the belief that something objective happens there.
There are also pretty hefty philosophical problems with the doctrine of transubstantiation, even assuming we accept that a substance's properties can become detached from that substance and attach themselves to another one, which is what transubstantiation requires. For example, the doctrine states that the entirety of Christ's body is present in the consecrated elements. But it would follow from that that, if Mass is being said in two churches at the same time, the whole of Christ's body is present in two places at once, which is impossible. Another problem is the question
how Christ's body gets to the altar. The traditional Catholic teaching is that Christ's body does not move from heaven to the altar - rather, the bread that is already on the altar is transformed into Christ's body. But it's impossible to see how one substance can be transformed into another one
that already exists, let alone how it can do this without inconveniencing the original. If Christ's body is in heaven, and now it is here on the altar, how can that occur without something happening in heaven?
One could multiply such objections. However, these are objections to the doctrine of transubstantiation, not arguments that the Eucharist is purely symbolic. One could hold that something supernatural genuinely occurs at the Eucharist, and it is therefore not purely symbolic, without holding the doctrine of transubstantiation. I don't really know what motive a Christian would have for holding that nothing supernatural happens at the Eucharist at all, on the assumption that a Christian believes in supernatural stuff happening at least sometimes. I suppose that an extreme biblicist might be unwilling to accept the notion of divine action or revelation in a non-biblical context or something like that. Or an extreme Lutheran who believes that (an individual's) faith is the only thing that matters might think that, if God were to do something objective in the Eucharist or any other context, that would override people's faith.
As for Catholicism being the one true Church, again, that's a Catholic claim. And for evidence of the claim, I meant Biblical evidence, evidence from the Early Church, exc. Basically, is it reasonable to believe, from a Christian perspective, they could be wrong?
You're surely familiar with the Catholic arguments from things like Jesus calling Peter the rock on which he would build his church and so on. And of course a Christian could hold that these arguments are wrong, since a Christian is not obliged to believe that Jesus really said such things, let alone (if he did) that he meant what Catholics think he meant by them. I think a Christian who believes that everything in the Bible is true should be led in a more Catholic direction. If one thinks that the views of the church fathers matter, then again they too lead in an approximately Catholic direction, at least compared to Protestantism. But I don't see that they lead more in a Catholic direction than in an Orthodox one or indeed a Nestorian or Coptic one.
Moreover, if by "one true church" is meant the idea that everything taught by the Catholic Church is true, I can't see any very good arguments for that, from any perspective.
So I think it's perfectly possible to be a Christian and reasonably think the Catholics mistaken. Of course, the same thing can be said of any other Christian church or Christian belief.
Well, I know Protestant Theologians (Who know a LOT more than me) have argued against that view, and there's no way they are simply totally unaware of these things. So, how have they defended this positions? (I'm asking Plotinus here, I know Jehoshua would just say "They can't"

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Surely the most fundamental argument a Protestant can make against any Catholic arguments from patristic practice is: just because the Church Fathers thought something, doesn't make it true! If you think that the Bible is what matters, then while patristic testimony might be valuable and worth considering, it's hardly infallible. So just because various patristic authors believed in something like transubstantiation is neither here nor there - what matters is what the Bible says. Also, you'll notice in the quotations given on the page I linked to that Ignatius states clearly that some Christians (identified editorially as gnostics, although that is uncertain) do
not believe that the bread and wine are transformed into Christ's body and blood. So belief in transubstantiation (or something like it) was not universal among early Christians. Of course, those who denied it were regarded as heretics (though not for this reason). One can't help concluding, then, that there was a diversity of belief and practice in the early church. Those who held views we might think of as "Catholic" were those who "won", but that doesn't necessarily mean that they were the ones who understood the Christian revelation in the most authentic way. Perhaps they were just better at arguing!
Now personally I would be inclined to think that the "Catholic" viewpoint was the mainstream one and the one that did most faithfully develop the New Testament point of view. However, a Protestant could perfectly easily deny that without any inconsistency.