[exDemMom]

Any dividing line drawn significantly after conception is really unsupportable. Some dishonest or easily influenced individuals may point to the high rates of human miscarriage, and the significant number pregnancies that end without implantation successfully taking place, but that’s a truly illogical argument with no comparable basis in fact - the fact that a child may suffer from SIDS, or that historically the MAJORITY of children born never reached adulthood, does not imply that a unique individual person did not exist prior to leaving infancy or childhood

You cannot point at *any* event and say that is the start of life, because there is no such point. Life began billions of years ago, and we all exist on the continuum of that original life. The sperm and egg are alive before they fuse to become a zygote. As a scientist, I have grown millions, maybe billions of human cells for experimentation in the lab. They are alive. They are human. They are not, and will never be, human beings. In some cases, they even form higher level structures very much like tissues in an intact organism. But this low level of differentiation is not sufficient to make those cells into a person.

I see a number of things that people almost worship, which are hardly even significant. They worship the fusion of sperm and egg, as if cell fusion is some magical event--it is not. Any two cells can fuse. Also, it is possible to take stem cells and induce them to start embryogenesis--without any kind of fusion event taking place. A person resulting from that process would still be as human as anyone else. They worship the new mixture of DNA, as if it is something really special--it is not. Unique configurations of DNA are all around us, and mean quite little as far as personhood is concerned. If a thousand people were cloned from identical cells and all had identical DNA, they would still be separate people regardless of their lack of uniqueness.

I can go on and on, because I have observed first hand that human + alive does *not* equal human being. The defining attribute of a human being is that it has a nervous system that enables it to sense and interact with the world around it. The time that occurs has been thoroughly observed and documented. The nervous system starts to form with the folding of the neural tube at 3 weeks after conception, and sometime between 3 and 5 weeks, that nervous system takes over control of the body and begins sensing and responding to its environment. At that time, what was merely human and alive and not significantly different than the millions of cells I have grown for research becomes a human being.

[bert]

Yes, but it was Jeb that killed Terry

[don-o]

As a scientist, I have grown millions, maybe billions of human cells for experimentation in the lab.

Perhaps you could back of the science and consider common sense. When a sperm and egg unite, a process begins - a natural process that, if not interrupted, will result in a baby. This cannot be disputed.

[TigersEye]

The sperm and egg are alive before they fuse to become a zygote.

But they do not have the characteristics I described in post #31. Sperm and ovum do not have a unique DNA sequence. They don't even have one complete DNA sequence and they can't replicate their own cells. Those are the defining characteristics of a discrete individual living being and the type of DNA defines the type of being. Those characteristics come into existence at conception.

[TigersEye]

The nervous system starts to form with the folding of the neural tube at 3 weeks after conception, and sometime between 3 and 5 weeks, that nervous system takes over control of the body and begins sensing and responding to its environment.

There is nothing special or magical about that. It's just autonomic nerve function. Even the nervous system of a corpse can be stimulated.