May I respectfully point out that most of the above which excludes Cain and Able is a common speculation that has nearly nothing to do with the important Catholic doctrines of Adam and Eve
For example, the idea that man “developed intellectually enough” or “that man was intellectually advanced enough” is not the Catholic definition of an immaterial, immortal, spiritual soul with its powers of intellect and will. It is the soul which makes a being human. Enough intellectual ability is not the Catholic criteria for a human being to be called to share, by knowledge and love, in God’s own life.
Another example, “At some point in human history man had developed intellectually…” – When one thinks about this, how could there be human history before Adam and Eve? Often we hear stories about pre-human history; but a pre-human, which could be anything, is definitely not the same as a true, real, fully complete human being whose nature is soul/body, spirit/matter, rational/corporeal.
As to the “people” outside of the Garden, they would have to be children of Adam and Eve who had left the Garden. Remember that God had blessed the union of Adam and Eve without limitation.
The official teaching regarding Adam and Eve is found in
Catechism of the Catholic Church, Second Edition, ISBN: 1-57455-109-4
Paragraphs 355-421. One can also put Adam, etc. in the Catechism’s search bar in link
www.scborromeo.org/ccc.htm
Blessings,
granny
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