The biological cycle of man is divided into "sevens," and each first period of the new physical and spiritual cycle of man's life is designated symbolically by a number, the "day" eighth.  

"Eight" is a symbol of the beginning of a new "Seven," the beginning of a new fullness of knowledge and the incarnation of the Will of God.

Negative Meaning.

"The Eighth Beast" is a symbol of the full expression of evil, of a brutal political, predatory economic, and false religious system.