To recap so far, Hume has presented a severely truncated view of human rationality that he wants to use to attack likely post Cartesian view of the intellect. As Balto said, the
res cogitans and any concept of innate ideas. Locke also rejected the concept of innate ideas, proposing that only sense impressions generate intellect. We are a tabula rasa or blank slate.
My response is that this has no impact on Aquinas or Aristotle since they agree with Hume and Locke that the intellect has its origins in sense perceptions but is not reducible to them.
What Hume attacks next is the concept of causality. Specifically the notion that you can deduce anything about a cause based on an effect. He believes there is no necessary link between cause and effect. Only custom leads us to think that because B follows A that there is a link.
I think what is problematic here is the idea of necessary. I think he places the bar way to high when determining what a necessary idea is. He wants necessary to mean some kind of mathematically necessary formula that would be true in all worlds apriori.
Aquinas and Aristotle have the concept of proportionate causality where you can deducing something about the cause from the effect. The cause is in the effect either emminently, virtually, or formally. Edward Feser has a
blog post that contains information about these types of proportionality.
Now, Hume seems to be attacking the notion that one can tell what is the cause from the effect alone. But the arguments for the existence of God on not based on whether we can scientifically deduce cause A from effect B, but are based on metaphysical principles presupposed by science. From the post, he says:
…because for A-T we cannot just go around attributing “virtual” or “eminent” features to a thing willy-nilly. In particular, the A-T understanding of causality would in no way license the conclusion that just any old natural process could in theory have immanent causality or life within it “virtually” or “eminently” and thus cause life to exist “formally” in some first organism. The nature of causality as such is a metaphysical question, but what specific causal powers things actually have is an empirical question.
Aristotle and Aquinas derive metaphysical principles based on what we come to know as general metaphysical rules that hold true for all of physical phenomena. Truths such as proportionate causality or the idea that everything that is moved is moved by another, or the law of non-contradiction. They don’t arrive at these metaphysical principles apriori, but a posteriori. Are these principles capable of being disproved? I would say that they are. But if they were, we would have some serious problems on our hands and would likely have to jettison any solid concept of reason.
But to sum up, our experience tells us that B follows A. That when a billiard ball hits another billiard ball, that a chicken doesn’t just pop out of nowhere where the struck billiard ball was. And even if it did, we would not immediately assume that the appearance of the chicken was without a cause. We would go through a long list of possibilities before admitting there was no cause. And even then we would probably never admit that there is no cause, only that we will never know the cause, but we would not doubt that there is one.
Anyway, the cosmological arguments build on these principles derived from experience that we have no good reason to doubt unless one had a prior and arguably unreasonable desire to reject (for example, a desire to get rid of a field of knowledge that seems to give too much credibility to revealed religion.) And if they consistently rejected such principles, they would also undercut the very possibility of science.
God bless,
Ut