Which People are People? Fundamental Questions

In the state of New York, 1 out of every three pregnancies ends in abortion annually.  For African Americans, this statistic is even higher: 1 in 2.

This isn't adequate, though; in this state of New York, a bill put forward by the present Governor, Governor Cuomo, called the Reproductive Health Act, postulates removing the few controls on abortion which exist in New York: abortion available throughout the term, legalization of abortion providers that are not licensed medical personnel, and the stripping of the state penal code of any judicial and legal recourse a woman might have if she experiences either malpractice during an abortion procedure or even the death of her unborn child due to domestic violence (she would still have recourse to sue for personal injury, but no harm to the child could be prosecuted).  

Over time, people have defined human life based on how they feel about it.  Even the scientists in my life, and they are many (as my husband is a graduate student in experimental physics), do not claim to be able to define life scientifically or coherently.  A person is a person based on what?  How the majority of society feel about them?  

In the Constitution of the United States, African American men are defined as three fifths human.  This was not changed for nearly a century.  Based on what?  --How many people felt that being racially white makes you a full or real person.  In Nazi Germany, a Jew or a Pole was not defined as a person.  (Those of African descent were also considered sub-human in the evolutionary process.)

Are these definitions wrong because we feel differently about them now, or were they wrong even when they were the status quo?  

I do not like politicizing; this blog will not become that kind of forum.  But this question of the definition of a human being, I find, is being answered in all sorts of ways by all sorts of people, solely based on their feelings... and this is an important question for all individuals everywhere to answer.  Who is a human being? What constitutes a person?  Is the definition of a person whatever the state or society endorse at any given period?  If so, why does history condemn this practice?

Speak for life; speak for those who have no voice.  Remember the past: let it inform your present.  Let's stop repeating this terrible mistake of human history.