Hi my question is about what we know about things we know because they are what they are or we know because they are what we perceive them to be. I came to thinking about this when I was thinking of spinning a cube fast enough to appear to be a sphere. The problem I had was that if what we know about things is gathered by how we perceive them, i.e. through empirical investigation, then the sphere/cube problem would lead to a contradiction in conclusions as one group of people (those that see the cube in motion) would say that it is a sphere whilst another group of people (those that see the stationary cube) would say that it is a cube. So our knowledge of things cannot have come from how we perceive them as our perceptions are obviously misleading and can lead to contradictions. This leads me to think that what is is separate to what our minds perceive or what our minds think is but then I come across the problem of the gap between reality and our minds. How do our minds detect what actually is in reality without some sort of perception and therefore not coming across my first problem? If everything that is is not actually some sort of perception, how do we know anything? And if everything we know is actually some sort of perception, how do we know that anything we know is actually knowledge and now just a certain perception?