Human Life Begins at Fertilization

I’d like to thank e.gibson for being willing to debate an important scientific topic with me: does human life begin at fertilization? I should have started with some basic definitions, but thankfully e.gibson correctly understood the meaning of my words. For clarification’s sake however, I’ll define some of the more important words here: Chromosomes: Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.[1] DNA: DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms.{2} Sperm and Oocyte: Male and female sex cells, respectively. Zygote: e.gibson defined “zygote” based on the Google definition: “a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.”[3] Embryo: in humans, the developing organism from fertilization to the end of the eighth week.[4] Fetus: In humans, the unborn young from the end of the eighth week after conception to the moment of birth, as distinguished from the earlier embryo.[5] Organism: I’ll take e.gibson’s lead, and use Google’s definition,[6] which is comparable to embryology textbooks: 1: An individual animal, plant, or single-celled life form. 3: A whole with interdependent parts, likened to a living being. Note that a one-celled individual animal can be an organism. Noted embryologists O’Rahilly and Muller place the beginning of the life of a new organism at fertilization:[7] "Although life is a continuous process, fertilization (which, incidentally, is not a 'moment') is a critical landmark because, under ordinary circumstances, a new genetically distinct human organism is formed when the chromosomes of the male and female pronuclei blend in the oocyte." The human entity at this stage has at least two key characteristics: A unique DNA fingerprint: Each of the entity’s cells has a unique, complete genome of 46 chromosomes (unless there is a chromosomal anomaly like Down syndrome, in which the child has 47 chromosomes). Whole human organism: The only thing this entity needs is a proper environment and adequate nutrition to develop herself as an individual member of the species. There is no substantial change in the human organism from fertilization until death. It is an organism whose development is being driven from within. It is developing itself to the next stage of the organism according to the nature of the organism. The organism is also integrating its body parts for the good of the whole. This is what distinguishes the zygote from other somatic cells. E.Gibson makes the biological mistake of confusing parts with wholes when he classifies the zygote as mere cells, instead of as an organism. As Scott Klusendorf points out in his book, The Case for Life,[8] "The difference in kind between each of our cells and a human embryo is clear: an individual cell's functions are subordinated to the survival of the larger organism of which it is merely a part. The human embryo, however, is already a whole human entity. True, it's an immature human, as is an infant, but it's a whole human organism nonetheless...It makes no sense to say that you were once a sperm or somatic cell. However, the facts of science make clear that you were once a human embryo." Some questions for my opponent on species classification: At what point in development do you believe a zygote/embryo/fetus becomes a member of the human species? What was it before? I’m going to close by quoting some of the other top embryology textbooks now, as well as the most respected pro-abortion-choice philosophers in the world today. I realize that appealing to scientists or philosophers is not in itself an argument. They have studied these things and they should know, but they could also be mistaken. But I’m going to need some actual evidence that shows all the embryologists and pro-abortion-choice philosophers are wrong. Drawing a mistaken conclusion from a 9th grade textbook isn’t going to cut it. Modern Teaching Texts on Embryology "Human development begins at fertilization, the process during which a male gamete or sperm unites with a female gamete or oocyte (ovum) to form a single cell called a zygote. This highly specialized, totipotent cell marked the beginning of each of us as a unique individual."[9] "A zygote is the beginning of a new human being (i.e., an embryo)."[9] "[The zygote], formed by the union of an oocyte and a sperm, is the beginning of a new human being."[10] "Human embryos begin development following the fusion of definitive male and female gametes during fertilization... This moment of zygote formation may be taken as the beginning or zero time point of embryonic development."[11] Pro-Abortion-Choice Philosophers Peter Singer: “It is possible to give ‘human being’ a precise meaning. We can use it as equivalent to ‘member of the species Homo sapiens’. Whether a being is a member of a given species is something that can be determined scientifically, by an examination of the nature of the chromosomes in the cells of living organisms. In this sense there is no doubt that from the first moments of its existence an embryo conceived from human sperm and eggs is a human being.”[12] David Boonin: “Perhaps the most straightforward relation between you or me on the one hand and every human fetus from conception onward on the other is this: All are living members of the same species, homo sapiens. A human fetus, after all, is simply a human being at a very early stage in his or her development.”[13] Sources: 1: http://www.genome.gov... 2: http://ghr.nlm.nih.gov... 3: http://bit.ly... 4: http://bit.ly... 5: http://bit.ly... 6: http://bit.ly... 7: Ronan O'Rahilly and Fabiola Müller, Human Embryology and Teratology, 3rd edition. New York: Wiley-Liss, 2001. p. 8. 8: Klusendorf, Scott. The Case For Life, 1st ed. Wheaton, IL: Crossway Books, 2009. 38. Print. 9: Keith L. Moore, The Developing Human: Clinically Oriented Embryology, 7th edition, Philadelphia, PA: Saunders, 2003. pp. 16, 2. 10: Keith L. Moore, Before We Are Born: Essentials of Embryology, 7th edition, Philadelphia, PA: Saunders, 2008. p. 2. 11: William J. Larsen, Essentials of Human Embryology, New York: Churchill Livingstone, 1998. pp. 1, 14. 12: Peter Singer, Practical Ethics, 2nd ed. (Cambridge: Cambridge University Press, 1993), 85-86. 13: David Boonin, A Defense of Abortion, (New York: Cambridge University Press, 2003), p. 20