Architecture is mimicry. Every shape created by mankind is a mimic of organic forms found in the nature. Either its curvy, rectalinear, firm or fluid, all the forms are derived from the mother nature. Imagination can be a part of this process, but humans do not have the ability to create from ground zero. Thus, as a branch that is directly connected with creating new things, architecture can not be completely unique. Its source is always and will always be nature.
The black&white image I used in the second image is from a painting I saw in Kunsthaus, Zurich. Don’t know the artist.