Questionable analogy arises when you are able to point to one or more significant differences between the two cases being compared in an analogy. The crucial - and very worldview-dependent - question is: do the relevant differences between the two cases outweigh the relevant similarities? If so - the analogy is weak and the conclusion is only weakly supported; if not, the analogy is (relatively) strong, and the conclusion enjoys some support.
4. Treating addiction to heroin with methadone is like treating addiction to scotch with bourbon.
[We don't treat alcoholism with alternative forms of alcohol.
[/.. We should not treat addition to heroin with methadone.
5. Until the age of viability (ca. 25/26 weeks), the fetus cannot survive outside the mother's womb. She acts like a life-support system -- one unique in all the world, for it is the only one the baby can depend upon for survival until it is ready to exist in the world on its own.
To remove the fetus from the mother's womb, with the result that it dies, is like pulling the plug on a patient's life support. The latter is murder. Therefore, the former is murder.
6. The mother is in the same relation to the fetus as a woman whose blood and kidney types may be the unique combination necessary to save an ailing person's life.
If the ailing person's family kidnaps the woman who can save that person's life, forcibly ties in her bodily systems with those of the ailing person, so as to save that person's life --
would we not say that the woman would be very nice to stay in the hospital bed for however long it took to save the ailing person's life -- but that she has no moral obligation to do so?
On the contrary, just as the kidnapped woman has every right to disconnect the tubes that tie her to the ailing person, get out of the hospital bed, and leave --
so the mother of the fetus has very right to sever her connection with the fetus, if she so chooses.
(Based on Judith Jarvis Thompson)
7. Education cannot prepare men and women for marriage. Trying to educate them for marriage is like trying to them to swim without allowing them to go into the water. It cannot be done.
8. Bill Clinton has no experience of serving in the military. To have Bill Clinton become president, and thus commander in chief of the armed forces of the United States, is like electing some passer-by on the street to fly the space shuttle.²