That is actually an inference.
Don't believe me? Read Genesis again.
Recently, other folks here have mentioned the 'flaming sword' anachronism, the serpent 'eating dust', and the actual statement by God that 'man had become like us, knowing good and bad' (i.e. the serpent did not lie).
If your curiosity is peaked by re-reading Genesis, think about what would have happened during the 'flood' to the rivers surrounding the Garden of Eden. If the Garden was destroyed, why would you expect the rivers to remain intact? Why could its location be remembered by the confluence of four rivers after the population was displaced in time and distance by the 'flood'?
Creative storytelling, that's how.
So, back to the subject... the bible says lots of creations were good, but God never referred to any, including Adam & Eve, as perfect.
What does perfection mean anyhow?
cellomould
"In other words, your God is the warden of a prison where the only prisoner is your God." Jose Saramago, The Gospel According to Jesus Christ