what is the endless house?

The endless house to me could be the human mind. The mind, in a sense is "the last refuge for man as a man". Our minds are our last refuge and the one thing that will always be our own. There are many possibilities of what the endless house could mean, it is a somewhat vague term and is very hard to put a finger on exactly what it means.

swans reflecting Elephants

I think it is a very creative painting. The artist used his understanding of the human minds ability to percieve things and search for familiar patterns to portray the swans reflection as an elephant.

Lennon

"a dream you dream alone is only a dream. A dream you dream together is reality."
-John Lennon

I think what John is saying is that when people dream together it can be real, because in the end what really seperates a dream from reality? I believe a dream can be considered just as real as experiences you have while awake. Everything we do or see is just an experience, a perception of the mind. Therefore it is difficult to determine what is real and what isnt.