When I encounter a rock is there a two way flow of information? The rocks rockness reaches out and meets my me-ness at some point and information about the rock is sent to me via my senses. Is there a reciprocal flow of information to the rock? I'm finding it hard to express my thoughts about this. Is there a 2-way communication between me and the rock? Steve B

In perception, you are affected by the rock. You are changed, and the rock is the cause of the changes. Change means that you acquire some different properties. Now, some of your properties are intrinsic and some extrinsic. Philosophers have a hell of a time trying to explain that distinction clearly, but, roughly, an intrinsic property of something has to do purely with the situation "inside" it as opposed to elsewhere. Since your conscious states, and other sensory and cognitive states, are changed, you have undergone intrinsic change, and, as you say, your new intrinsic states bear information about the rock in virtue of its having caused them.

Now, the rock is also changed intrinsically by the encounter. Your gravitational attraction affects it some, and light bouncing off you hits the rock and changes it in various slight ways.

Unlike you, however, the rock is unable to collect and decipher the traces of your presence that impact it, and so your effects upon the rock's intrinsic properties are subtle and diffuse. However, the encounter has also changed some extrinsic properties of the rock: it now has the properties of being perceived, of being thought interesting, and so on. The rock has no clue of this, but in fact you have elevated it into participation in the world of thought.

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