Symmetric 4 x 4 square

Martin Gardner (1914-2010) studied philosophy and was interested in everything.  For 25 years he wrote the "Mathematical Games" feature for Scientific American.  At Magic Dragon Multimedia, Jonathan Vos Post has collected many of the poems Gardner featured in his column over the years.  Here is a symmetric square poem from February, 1964.

            C U B E
            U G L Y
            B L U E
            E Y E S