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“So Bob, what do you like to do for fun?”
“I like playing role-playing games”.
“Oh yeah?”. My husband, an RPG aficionado, clearly had his interest piqued. “Which ones?”
“God of War, or Assassin’s Creed”.

I frowned, puzzled. I’m no gamer, but even I knew that God of War and Assassin’s Creed were not RPGs. My husband explained to me later that this mistake, where people designate certain games as RPGs when they are not RPGs at all, is not uncommon. Presumably, it stems from the fact that RPGs were the first games to popularise the concept of “levelling up”. Over time, more games in different genres started including levelling up in their designs, which led to them being confused with RPGs, even though they lacked most of the defining characteristics of RPGs. Levelling up was originally a necessary condition for an RPG (every RPG includes levelling up) but it became (wrongly) known as a sufficient condition for RPGs (every game that has levelling was called an RPG).

This mixing up of necessary and sufficient conditions can happen a lot. For example, every single heavy metal song features electric guitar: electric guitar is a necessary condition of heavy metal. However, it would be wrong to say that electric guitar is a sufficient condition for heavy metal music because then you’re saying that every song to feature an electric guitar is a heavy metal song, which is clearly wrong.

Misunderstanding the distinction between necessary and sufficient conditions happens all the time, in conversations about so many topics. Here are a few examples of how this can play out when discussing the topic of abortion.


The constant talking past each other that pro-life and pro-choice people tend to do about religion and abortion can be cleared up if we think about the topic through the lens of necessary and sufficient conditions. Pro-choice people generally think that the unborn are not the moral equals of a born woman and/or that a woman’s right to decide what to do with her body outweigh the foetus’s right to life. This means that for many pro-choice people, logic dictates that abortion is justifiable, and therefore the only reason someone could disagree with that is if they are appealing not to logic but rather to something like faith or religion. From a pro-choice person’s point of view, religious belief is therefore necessary to oppose abortion, and they often assume that any and all pro-life convictions must be (at least partly) founded in religion.

Pro-choice people can be somewhat forgiven for this misconception due to the fact that some (though not all) pro-life people do actually appeal to religion or faith in making their case for the unborn. However, even when pro-life people do appeal to religion in their pro-life advocacy, the vast majority of them see religion as simply being sufficient to oppose abortion. In other words, they do indeed believe that appealing to religion is one way to convince people to oppose abortion – but they (for the most part) don’t think it’s the only way. In their view, convincing people to adhere to a particular religion, or pointing out that abortion is prohibited by a particular religion, may be sufficient to convince someone to oppose abortion, but this does not mean a religious viewpoint is necessary to oppose abortion.

Pro-life people can help clear up the confusion by saying something like “Yes, I’m sure for some people, their religious convictions are what leads them to oppose abortion, just as religious conviction leads them to oppose terrorism, or fraud. There are non-religious reasons to oppose all those things, however: I certainly oppose all those things and I don’t oppose any of them for religious reasons”.


Many discussions amongst thoughtful pro-choice people (and between thoughtful pro-choice and pro-life people) involve the role of consciousness in determining the right to life. For the reasons outlined in these two posts, I don’t think that consciousness is a particularly good barometer of who does and doesn’t have the right to life, because there are just too many cases of non-conscious humans who have the right to life. In other words, consciousness is not a necessary condition for the right to life.

Having said this, many people (both pro-life and, more often, pro-choice) make strong arguments for why having consciousness gives you the right to life. These people often think it’s wrong to kill animals, or at least some animals, and their rationale is based on consciousness arguments. These arguments show that consciousness is a sufficient condition for having the right to life – but far too often, pro-choice people jump straight to acting as though they have shown that consciousness is both necessary and sufficient.

I find this is an easy thing to point out, and most pro-life people completely fail to do so. When faced with consciousness arguments, most pro-life people seem to push back on consciousness being a sufficient condition for the right to life (“Do you really think we have equal rights to a squirrel?”, etc). Yes, it seems odd to think that humans have equal rights to squirrels, but there’s no reason why someone might not honestly think squirrels and humans have equal rights because they are both conscious. That still doesn’t tell us anything about whether people or animals that aren’t conscious do or don’t have rights!

Instead, I find we make much more headway to leave aside the question of whether consciousness might be sufficient to grant rights, and instead to question whether or not consciousness is necessary. There are plenty of examples of human beings who are not (currently or ever) conscious, and they are described in the posts linked above. The fact that these humans are still considered equal to conscious humans suggests that consciousness is not necessary for equal rights. So it’s ok to concede that consciousness might be sufficient to grant rights, and focus instead on why pro-choice people think consciousness is necessary to grant rights.

Savita Halappanavar

We in the Minimise Project have not explicitly addressed the tragic case of Savita Halappanaver, and this is partly because our focus is on reducing abortions and having better converstations about abortion. However, the case is relevant here, because the reason conversations about the case of Savia Halappanavar can be so difficult is because there is a complete failure, on both sides, to distinguish between necessary and sufficient conditions.

The pro-choice argument goes: (1) If Savita’s pregnancy had been ended on the Tuesday or even the Wednesday, she would have survived. (2) Savita’s pregnancy was not ended, because of the Eighth Amendment. (3) Savita later died, and her death was because of the Eighth Amendment. 

The typical pro-life response to this reading of the facts is to say that Savita died of sepsis, that her doctors missed many opportunities to diagnose her of sepsis in time to save her life, and therefore did not intervene in time.

The pro-choice argument as presented above argues that abortion was a necessary condition for saving Savita’s life. The standard pro-life response is to argue that abortion was neither necessary nor sufficient to save Savita’s life, and that instead what she needed was for her sepsis to be diagnosed and treated. However, pro-lifers tend to forget that the treatment of sepsis always includes removing the source of the infection as quickly as possible, which in this case would have meant ending the pregnancy. So pro-choice people are not correct to claim that abortion was necessary to save Savita’s life, but pro-life people are wrong to deny that abortion would have been sufficient to save Savita’s life – it probably would have been. (It should be noted that sepsis treatment also requires the administration of antibiotics in addition to removing the source of the infection as quickly as possible). Distinguishing between whether the medical procedure that ended the pregnancy was necessary or sufficient to save Savita’s life would be very helpful in having conversations on this topic, and on other topics of difficult cases in pregnancy, particularly where the medical team misses relevant facts).