Well I thought that was the premise, to unravel the mystery of origin. You acknowledge that we do not have reason to think that our reasoning can be true.
Read what I said again. I said that we *do* have reason to think it at least partially valid for conditions in which we evolved and for others, a skepticism and thorough testing provides what we cannot know without them.
Well. Well. Now you are pointing to wrong and Ideas.
We come back to the same point.
We qwell know that our senses don't give perfect information about the world around us. We cannot see infrared or ultraviolet. We cannot detect radio waves, or most types of radiation. We cannot hear outside of a certain range of frequencies.
So, no, there is no reason to think we get the whole picture, ever. But we can, and do, find ways to detect and understand these aspects of the world through extending our senses in various ways.
And, again, we do know the tendencies we have for irrationality. We know rationality is hard and needs to be trained. But it is possible and desirable if we want a better understanding of the universe.
But why we would expect our ideas to be correct without testing and careful thought is beyond me. It is quite clear that being careless leads to wrong ideas all the time.