I would like to share a tool that will help you make a case for the intrinsic value of the unborn. The embryo differs from a newborn in four ways, but these differences are not significant in the way that abortion-advocates need them to be. The acrostic SLED is a helpful reminder of these non-essential differences. People discriminate against the embryo because of…
- S ize: People want to disqualify the humanity of embryos because they are so small, especially in the early stages of development. I had a premed student look at me in disbelief when I argued for the humanity of the embryo at the cellular level. He felt the microscopic fetus in a petri dish was not human. I asked him, do large people have more rights than small ones? Men are generally larger than women. Do they deserve more rights? Is Shaquille O’Neal more of a person than Hillary Clinton simply because he is larger? Surely no one would argue that it is less a crime to beat a small child than it is a large one. Clearly, the size of the fetus is not the issue.
- L evel of Development: True, the fetus is less developed than a newborn, but why is this relevant? Is a four-year old girl who has yet to develop her reproductive system less human than a 17 year-old who has? Is that same four-year old less human because she does not match the intellectual prowess of a teenager? Clearly not. It is one thing to say that human beings at a certain stage of development have the inherent capacity for critical thinking. It is quite another to assert that your right to live depends on your immediate capacity for intelligence. Yet, if abortion advocates are correct, that rationality and self-consciousness define the morally significant person, then why shouldn’t greater rationality make you more of a person? Consequently, the intellectually and artistically gifted would be free to maximize their pleasure at the expense of those less intelligent. The all-important question becomes “What kind of mind merits human value and who decides who qualifies?” Do smart and articulate people have the right to define the small and vulnerable out of existence simply because they are in the way and cannot defend themselves? Such a view is elitist and exclusive. It violates the very principle that once made political liberalism great: a basic commitment to defend the weakest and most vulnerable members of the human family.
- E nvironment: Where you are has no bearing on who you are. Did you stop being you when you rolled over in bed last night or when you walked from the car to your den? If not, how does a simple journey of seven inches down the birth canal suddenly transform the essential nature of the fetus from non-person to person? A baby girl named Rachel was born at 24 weeks gestation. (That is barely six months into the pregnancy.) At the time of her birth, she weighed less than a pound and could fit into the palm of your hand. The hospital staff worked heroically to save her life and now she is a healthy young child. But let's assume that instead of saving baby Rachel's life at 24 weeks, the doctor came to her room and killed her while she was resting in her father's hand. We would consider that an outrage, wouldn't we? But do you know that the same baby Rachel, that very same baby girl, can be killed through legalized abortion through all nine months of pregnancy simply because she is located six inches away in her mother's womb? Ladies and gentlemen, your right to live is not based on your current address. 
- D egree of dependency: If viability makes us human, all those who depend on insulin or kidney medication are non-persons and we may kill them. A newborn is dependent on his or her mother; should we be able to kill a newborn? Yet when it comes to the woman’s own unborn offspring, the moral logic of abortion advocates is that she has no responsibility to her child precisely because it depends on her for protection. In other words, he can be legally killed because of his need. This is absurd. 
Hence, there are only four differences (SLED) between the fetus and newborn and none of them relevant. In the past, we have discriminated on the basis of skin color and gender. Now, with elective abortion and destructive embryo research, we discriminate on the basis of size, level of development, location, and degree of dependency. We’ve simply swapped one form of bigotry for another.
In sharp contrast, the position I have defended is that no human being, regardless of size, level of development, race, gender, or place of residence, should be excluded from the human family. In other words, my view of humanity is inclusive, indeed wide open, to all, especially those who are small, vulnerable and defenseless.
 Stephen Schwarz first came up with the acronym SLED to illustrate these differences. Stephen Schwarz, The Moral Question of Abortion (Chicago: Loyola University Press, 1990) p. 17.
 Greg Koukl, Precious Unborn Human Persons, pp. 26-7
 Francis J. Beckwith originally came up with the wording of this sentence and the two previous.