I find it interesting that the definition of "incest" has changed. Western civilization's ideas about it have been Biblically defined. Obviously, after the Fall and before the Flood, a pair of children of Adam and Eve would have had to have married. There were dramatic changes in the ecosystem after the Flood, and the life span of people dramatically dropped. This change is noted in the Old Testament, and the Law given to Moses included God-approved and disapproved marriage relationships. Intermarriage within a nuclear family unit was forbidden (sibling/sibling, parent/child). This became known as incest. The Bible did not forbid marriage between first cousins. In fact, this was widely practiced amongst the European elite ruling class. It had the benefit of increasing family wealth and power. In Medieval times, marriage was more of a corporate merger, and females could only inherit property when they married. If first cousins of wealthy landowners married, the family name and land stayed in the family. This is how many clans initially formed. Albert Einstein's second wife was his first cousin, and this practice also helped the Rothschilds to build wealth and power, as well as some of America's Founding Fathers. In fact, later, laws were written to prevent these close marriages in order to break up these family monopolies. It was about money and power more than genetics.

Legalizing the Biblical definition of incest (parent/child) (sibling/sibling) would leave the child vulnerable to any pedo proclivities a parent might have and add to pedo normalization. It has also been shown that these types of relationships have a much higher risk of producing a child with birth defects. JUST SAY NO! Addendum: Whether you believe there was a flood or not, the early Christians did, and so the original laws regarding incest were influenced by this belief.