Serious Philosophizing

How does one perceive things? We're not interested in the mere scientific question of optics, but the far more fundamental philosophical question of how one's mind accesses the world. For the sake of clarity, let us replace the word 'things' with the word 'material objects'. What is a material object? Well, an object capable of being perceived, such as a chair, which is a good example as it is sturdy, and made of wood, and is roughly man sized and gives off no odor and tends not to make much noise of its own volition, and, along with tables and desks and lamps and books and pens and cigarettes and bottles of beer, tends to be around when serious philosophizing is being done.