I gave you numerous examples as an arguments to why it,abortion, can be seen as a continuum. It ranges from, but is in no way limited to, genetically derived problems (mother / zygote), to anatomic variations in the father / mother, to unknown/known substances making the environment of the uterus less hospitable to the zygote, to unknown/known toxicology and interactions of daily nutritional intake, pollution, to causes we as a society perceive the individual to be in control of: drugs, tobacco, alcohol, to herbal medicine, to overweight, to the medically inducedabortionto surgically inducedabortion. Understand that science knows all of these to be risk factors to the viable zygote, some factors more than others, dosis-dosis-dosis is the keyword and is argument for a continuum.
To hinder misconception of abortus provocatus, take the case of antiprogesterone and misoprostol which are used in pharmacologically induced abortions - These are not poisons in a traditional toxicological sense, but simply utilize the built-in mechanics (receptors, hormones) in the body to hinder the sustained hospitable environment of the uterus and induce labor - menstruation (expulsion of the uterine lining) and labor combined, put rather blunt. It does not take a phD to understand that some substances can affect said mechanisms (receptors, genetics). That is what I've given examples for in previous posts.
We can of course discuss whether this is a linear continuum (which I obviously don't think it is, interaction between the individual exposures) or some other model. To reduceabortionto a dichotomy is, to me at least, somewhat meaningless. To further ask me to 'prove' my argumentation within your fractally wrong world view is rather pointless - The outcome is not meaningful. At least not in any scientific enlightened way. If we differ in perception on the very basic scientific understanding of how the human body works how can we then have a meaningful discussion of the following step - morality ofabortion? To me these are linked - It requires extensive knowledge of the former to even begin discussion of the latter.
I would have hoped the above was comprehensible, thus allowing us to discuss the interesting parts, I repeat: "What is life? When does it begin? Does it even begin? These are open questions which are highly relevant if we're to discuss the next step, ending said life. When is it okay, when not, when is it even relevant to talk about ending life? What is conception etc etc." Insisting on putting these complex questions on top of a fractally wrong world view ofabortionis not furthering the discussion imho.
TLDR; The premise you set is too simplistic to allow a meaningful answer.