The solipsistic stance is often compared to living in a soap bubble.  Von Uexküll even used this analogy in talking of the Merkwelt.  But consider the square soap bubble (  It might think that its squareness belongs to it alone.  But from the outside we can see that no part of it has any independent existence whatsoever.  The square bubble exists only as a relatively stable equilibrium among the many tensive forces that exist between the surrounding more-or-less spherical bubbles.  Its squareness is entirely relationally constituted.  So to with the P-world, or the solipsist’s bubble.