Neil,
DQ: What I said is not inconsistent with this. Part of gaining the independence of mind to think for oneself is ceasing to be a slave to sense experience.
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?
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.
Notice that when thinking about things this broadly, there is no need of any empirical testing and observation. 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.
DQ: The perspective of the rationalist is greater than the one adopted by the empiricist. This is because the rationalist is able to embrace empiricism within his larger purview. He is an empiricist when it is rational to be an empiricist, and he is a non-empiricist when it is rational to be a non-empiricist.
Neil: My contention is that it is never rational to be a non-empiricist. It is never rational to forget that everything is based on sense experience. But that isn't to say we can't reason or seek truth, only that we do it as a means to utility, not an end in itself.
It depends on who you are, and what your purpose in life is. For some people, truth is indeed an end in itself.
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.
This too is a non-empirical truth.
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