Neil,
Neil: At bottom what do we have other than sense experience? Before you say concepts, can you affirm that all concepts are derived either directly or indirectly from sense experience?
DQ: I'll give you an example of how we can reason beyond the empirical realm.
Instead of, say, creating the category, "tree", and grouping a certain number of empirical objects into it, we can create a broader category, "thing", and insert every phenomena in the Universe in there. We can then use this category to uncover those traits and characteristics that all phenomena share - for example, that each and every phenomenon is limited in extent.
NM: How do you "uncover those traits and characteristics" of an abstract category that we cannot empirically observe?
By examining the logic involved. For example, we can logically deduce that things cannot exist independently of other things. At the very least, for example, a mountain cannot exist without not-mountain (i.e. the rest of the universe) .
At most you could uncover some traits of "things" in our world (and our anthropomorphic world). To extrapolate that every "thing" outside our world must have the same traits would be a misuse of statistics. To simply define abstract attributes for your abstract category gets you nowhere.
It has nothing to do with extrapolation and statistics. When it comes to the fundamentals, the logic that pertains to the "things" before us is identical to the logical that pertains to "things" everywhere else. A portion of the totality is always a portion of the totality, no matter where it is. It doesn't cease being a portion of the totality just because it is on the other side of the universe.
DQ: Notice that when thinking about things this broadly, there is no need of any empirical testing and observation.
NM: Because all the words (concepts) that you need already exist, right?
No, it is because fundamental knowledge can only come from the exercise of pure logic.
This is why I said that empiricists must exist before rationalists can come along.
They may have done, but it is irrelevant.
But just because these concepts already exist doesn't mean they are accurate. We have no way to test if these concepts are accurate because we can't test or observe them!
You can't think of a way to test how the concept of "thing" - defined as a portion of the Universe - necessarily refers to all phenomena in the Universe?
DQ: Empirical observation and testing can't add anything to the process. A thing is always a thing - whether it be a mountain, an electron, a thought, a person, a galaxy, or whatever. It doesn't matter form a particular thing has, or what empirical characteristics it might possess, it always remains a thing.
So straight away we are in the realm of pure logic, reasoning about matters that cannot be resolved through empirical methods. Our thinking has transcended the empirical realm entirely.
NM: "A thing is a thing" -- umm yes but what is a thing? This is useless in itself.
It is the key to all wisdom!
DQ: When it comes to matters of ultimate truth, we have no choice but to learn how to reason non-empirically. Science can never uncover what is ultimately true. It will always be limited in this way.
NM: I agree, science can never uncover what is ultimately true. But where do you think all our words and concepts came from? SCIENCE! We can never uncover what is ultimately true.
That isn't true.
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