There's a Disagreement Here

According to John Podhoretz:

The Talmud says any embryo-fetus under the age of 40 days is to be deemed "like water." That sounds harsh, though I believe its initial intention was to limit the emotional involvement of parents in the very early stages of pregnancy, when something like 25 percent of all fetuses naturally abort.

There is a wide variety of opinions in the Talmud on when a human life begins: at conception, 40 days later, 80 days later, at the beginning of labor, at birth, eight days after birth, or thirty days after birth. (In other words, if a pro-lifer left Judaism out of a supposed disagreement on abortion, we should try to get him or her back.)

Even the Union for Reform Judaism is willing to admit there's a Talmudic passage defending the claim that a human life begins at conception:

Antoninus said to Rabbi Judah Hanasi, “Does the soul enter the human being at the moment of conception or at the moment of formation?” The Rabbi answered: “at the moment of formation.” Antoninus said, “Can a piece of meat remain for three days and not putrefy? Obviously, the soul must enter from the moment of conception.” The Rabbi said, “This matter I have learned from Antoninus.”

-Babylonian Talmud, Sanhedrin 91b

Eric Cohen had some additional arguments.

One possible way to reconcile these opinions is to use fuzzy logic.

On the other hand … If subsidies cause a technology to become bloated and overpriced, maybe we do want to subsidize embryonic stem-cell research.