 Some Buddhists might question the premise that a human being exists from the time of conception onward. Some Buddhists in the contemporary West do not read the traditional teachings about reincarnation literally, and so would not have reason to accept that reincarnation happens at the moment of conception. Moreover, there are scientific reasons to believe that consciousness does not begin until at least the twentieth week of pregnancy (McMahan 2002, 267). There can be no reincarnation without consciousness. If we want both to believe in reincarnation and to accept what science tells us about the physical bases of consciousness, we should perhaps hold that reincarnation is a gradual process that slowly brings about a new conscious being that is connected with one who has recently died. This concept of a gradual beginning of life may be counterintuitive in some respects, but it harmonizes well with the fundamental Buddhist doctrine of no self. If we accept this understanding, then early abortion would not constitute killing a sentient being.