I will suggest that people use knowledge to explain, predict and manipulate the Thouse inputs that come from our senses, whether outer senses like smell, vision, hearing, touch, wormth, etc. or from our inner senses like therst, hounger, love, hate, etc are all will be called the phenomena. Phenomena, with correspondance to Kant's philiosophy, is our sensesexpriences.

I say that I perceive Through the surrounding usage of knowledge we try to understand our surroundings and not inner feelings, but we have a an unobservable barriar to the surrounding itself, because we or even our inner selves. We have no access to the surrounding itself. All our knowledge about the "surrounding" comes from our senses. We have perceptionspehnomena, visions, smells, touch, feelings and so on, which by some combination tell us something about but no access to the thing that creates the "outer-surrounding" or our "inner-state". Our knowledge is constructed from inputs we get from our sensesexpreinces.  For more than 2500 years of epistemology, [[The Historical overview of the phenomenological cage|nobody had found a reliable way to establish a relations between perception and the “surrounding”]]. To demonstrate the problem of the relations between knowledge and the worldsurronding, we may use the thought experiment of the “[http://en.wikipedia.org/wiki/Brain_in_a_vat brain in a vat]”. In this thought experiment, you are asked to find a reliable way to know if you really exists as you perceive it, or you are actually a brain in a vat, which gets it's sensory inputs from a computer, that simulate the perceived world.

The only thing we can say is that we percive. How this perception is constructed, I will suggest later own in this paper. as a result of our inability to go beiond our perceptions, I will call this principle '''"The phenomenological cage principle"'''.