On simplicity

Watching https://youtu.be/JV7K8CvA26I?t=27m37s, where the lecturer introduces i and tells us how suddenly "all equations were on the same footing" -- I had to ponder for a moment. In a way, physically speaking, if i is simply a reality just as, say, more dimensions or other things we don't automatically see, then all is indeed suddenly incredibly simple and uniform. However, the mathematical problem still remains as to the divide between real and complex numbers. The actual world may only know the concept of number (be it for us complex or not), we happen to know of this distinction. For us, mathematically speaking, it is still a complicated question exactly when, how, etc., equations have real solutions. So we see here, that "the burden" of knowing this distinction is what entails the complexity. But is this burden real? If nature knows only one concept of number, and we know two, are there actually two, between nature does not distinguish? I.e., does the distinction have natural effect? (One may say: yes, through our knowing of it.) Or is there just one, and we do not "know" of two, but "see" two. The idea here being: maybe the entire and only reason for our thoughts, being not reality itself, as it knows no distinction, is an initial "knowledge", what one may call a "focus", which naturally unfolds itself to all we now experience and see and understand and know.

Topics mulled over seem to be: Kant's epistemology, Leibniz' monadic view, mathematical complexity