A priori knowledge and intuition

[JJJJ]

Im currently reading a finnish textbook on Epistemology, and because the author seems to simply assume that intuitions and a priori knowledge exists without giving any sort of explanation, id like to know what kind of "proof" or explanations advocates of intuition and a priori knowledge usually give. Because for me it seems pretty unconceivable to follow the authors reasoning, if i cant understand his reasoning for the existence of a priori knowledge, as he makes no sense.

Has any of you ever debated, or heard any explanations for what exactly a person knows, and what he is aware of before he has ever experienced anything. Often i hear about how logic or math is somehow distinct from empirically gathered knowledge, and that somehow math and logic can be understood without any experience of the real world?? How can a person know that 2+2=4, if he has never experienced anything, and therefore can not be aware of the existence of anything that there can be "two" of. How can a person know what more or less means, if he has never experienced anything where there are differing amounts of anything?

Are there any attempts by rationalists and other apriorists to actually explain this, or do they all just do as the author of my textbook does, iow. assume that it exists? I really enjoy reading differing philosophical views, because it gives me some sort of joy when i can find the flaws in their reasoning, but this textbook doesnt even give any explanation, and thats why i thought that maybe some of you could help me out....

[DavidOdden]

Has any of you ever debated, or heard any explanations for what exactly a person knows, and what he is aware of before he has ever experienced anything.

Yes. I'm quite familiar with nativist ideas of language. What the actual content of that presumed knowledge is does vary from year to year. For example, according to some theorists in some years, humans have prior knowledge of grammatical categories such as "noun", "verb", also substantive properties such as "case" (and for some, there is a wide range of pre-known cases that is vastly larger than what exists in Finnish). What is granted is that the specific form of a case is not known a priori, thus you have to learn that in Finnish the partitive has a suffix -ta. However, you do know, by that theory, that there is such a thing as a partitive case. Things get murky when you try to pin them down as to the semantic content of this universal partitive (or, accusative).

These theories are actually pretty specific, all things considered. However, IMO the failing of the theories is that they don't shown that this knowledge has to be a priori.