You're already pre-supposing SO much. You're pre-supposing a shared objective universe which we are both capable of observing, perceiving, explaining, and pred

You're already pre-supposing SO much. You're pre-supposing a shared objective universe which we are both capable of observing, perceiving, explaining, and predicting. You are presuming a very specific order of causation and effect. All of these things are not 'given' in philosophy and can be manipulated to various effect (like hyperbolic geometries in mathematics). The argument that the universe exists apart from our perception or opinion of it is one position of many. (I happen to think that anyone who claims not to actually hold that opinion in the most deepest sense is a liar, but that's a different issue.) Philosophy is great for splitting hairs and breaking things down to their necessary essence - much like good programming does.