by wendy » Sun Sep 16, 2007 7:54 am
The mirror creates an illusion of depth behind it, by reflecting what's in front of it. That is, if the y axis is into the mirror, x,y,z become x,-y,z.
To create the illusion of two dimensions, one must study the thing as if nothing is let to move over or under the paper. That is, for a two-dimensional character on paper, one would be able to see all of its innards, and watch its lunch being digested!
To get the illusion of four dimensional view, (which falls on the retina as a 3d space, as 3d space falls on our eyes as two dimensional), one might suppose one is looking into a shape holographically, where ones attention can be brought to bear on any x-y-z coordinate without intervention of any other space.
When one looks holographically onto a 3d object, one sees it flat, as in the 2d thing above, and one might be able to look directly into the heart or the stomach. When one looks at four dimensions through the holograph, one sees only the visible surfaces by projection, the resolution of projection, as in 3d, is to be learnt.
Because the nature of four dimensions is so different, and that there is no real thing to see, one needs to create the objects in one's mind, using, among other things, mathematics and intuition, and a good deal of common and uncommon sense.
As 2d views on paper serve as either pictures (with gravity), and maps (without gravity) of 3d, so does the holograph serve these roles to 4d. Remember this.
Been there, done that, next.