https://www.sfsite.com/fsf/2007/gwng0704.htm
The main character is an unreliable narrator.
However consider all the veils that would have to be cast aside to understand reality:
1. The narrator could be lying to you. 2. The narrator could not understand what is truly happening. 3. The narrator may have mental models which are not accurate. 4. The narrator may be passing on inaccurate information or lies. 5. The narrator may be using words in a way that you think you understand, but do not. 6. The narrator may be expecting you to implicitly understand something that you do not e.g. we make certain assumptions about information because the Internet now exists, something similar exists in the world of the New Sun. 7. The narrator may be using the language of metaphor to describe something that is quite real but not what we think it is. 8. The narrator may not be one person. This won't make sense until you read the book. 9. The narrator could be telling you the truth, but you merely do not understand what he is really saying. 10. The narrator may not be lying at all, merely leaving out information that makes him look bad.
I could go on for many more points. I found thinking of Vernadsky's theories useful while reading it. If reading Gene Wolfe does not fire up your neurons, nothing will.
Again: the answers are in the text, it is not subjective in my experience, but you're going to have to think real hard on many different levels. Your understanding of the New Sun's world will be in flux for the duration of the book. Gene Wolfe gives you the answer, but he gives it once so you have to pay close attention. If something puzzles you, tuck it away and keep reading.