Jennifer Fitz, as part of a longer discourse on lying, offers a novel explanation of the principle of double effect. I think it's very approachable (and as far as I can tell, accurately represents Church teaching) so if this oft-misused principle has ever confused you -- please, check it out.
Hint: The principle of double effect is not just a way of saying, "We can do something bad if we can think up a good enough reason." Money quote: "That's the clincher of double effect -- there are two effects."
Double effect (also called “parallel effect”) is actually one of the two principles that work together to keep our moral system sane. The other is ‘ends don’t justify the means’, but that isn’t our topic today until way down below where I go out on a limb and guess things. Back to Double Effect:
#1 Reason to love Double Effect: It lets you take a shower.
Because here’s what: Showers and bathtubs are super dangerous. You could slip and crack your head open. And if the bathroom weren’t bad enough, you probably keep a stove and a water heater around the house, and perhaps even some kind of Vehicle of Death in your garage. (Or, if you are a Luddite, a Pack Animal of Death for your transportation needs.)
Double effect says that you are allowed to have all this and more! Because you aren’t actually trying to drown, scald or maim anybody. Those are unintended consequences of your perfectly reasonable efforts to stay clean, fed, mobile, and so forth. You’ll try to avoid those bad effects if you possibly can.
[What you can't do: If your enemy fails to drown in his bath, you can't hold him under. In fact you can't even lay out the bath things and light a scented candle in an effort to lure him to his death. You may only lead him to the tub for a legitimately good reason, such as to reduce the general stinkiness and discourage the spread of impetigo. Or perhaps so that he might unwind after a long day driving. you. crazy. But not to kill him. Barring circumstances we'll get to down the page.]
So that’s the use of double effect. It lets us do something good, even if there is a some risk of something bad happening in the process.
Now unless you suffer from deep scruples, you probable don’t lay awake nights wondering if your really did the right thing, caving in and buying a water heater. So where double effect gets famous is because it permits seriously dangerous action if there’s a genuine need for it.
You may not, for example, throw yourself in front of a bus in order to get that drat fly at last. (Even though the fly is germy and annoying, and you only want to give your beloved a peaceful picnic. Good cause, good action, but the risks are disproportionate. It’s a no-go. Hope the bus gets the fly, and live to swat another day.) But if it is to push your hapless child out of harm’s way, yes you may take the risk of your likely death in order to save the child. You aren’t trying to die. You hope to avoid dying. Everyone will be much happier if a guardian angel steps up and takes care of things.
And that’s the clincher of double effect — there are two effects: There is one thing good you are trying to achieve, and one bad bad you hope to avoid. Even if the bad effect is 100% likely barring supernatural intervention, you can’t be trying to achieve the bad effect.
There's more -- go read the whole thing. I think Jennifer's explanation is really helpful. Double effect is a seriously hard-to-understand principle. I think that's because there's a long separation in logic, and usually time and distance, between convincing yourself in the abstract that the principle of double effect is correct and morally right (which isn't so hard), and many of its applications, which can sometimes seem convoluted and (shall I say it?) jesuitical. To navigate some of these situations, it's like you have to wander through a long, twisty tunnel. At the beginning of the tunnel, the principle of double effect is well understood. At the end of the tunnel, you see the conclusions it leads to. The principle goes with you through the long, twisty tunnel, your only source of light, and it remains true all the time, but once you get to the end sometimes the conclusion is surprising and hard to understand.
Take one example: the end-point of Catholic moral theology with respect to ectopic (tubal) pregnancy. We wind up with what must seem a very bizarre conclusion:
- A persistent ectopic pregnancy creates a life-threatening disorder from the point of view of the mother.
- Yes, the out-of-place and growing embryo is a human being who deserves our protection.
- No, that doesn't mean that the mother doesn't get medical treatment, because she is also a human being who deserves our protection.
- So yes, she can seek treatment for it, treatment which will end the pregnancy and inevitably kill the embryo.
- But (assuming the mother wishes to remain true to Catholic moral understanding of life issues, and understands all this) she won't choose to use the drug methotrexate to end the pregnancy by killing the embryo, even though it is first treatment choice of many doctors and is probably physically the least dangerous option that doctors offer her,
- and it may be she won't even choose the least-invasive surgical method, salpingostomy (incision in the fallopian tube) followed by killing the embryo by removing it and its amnion;
- but she can choose salpingectomy, which is the removal of the section of fallopian tube containing the misplaced embryo,
- even though that removal inevitably results in the death of the embryo,
- which we knew all along was going to happen,
- and even though it would be objectively physically safer for the mother to undergo methotrexate or salpingostomy,
- and even though the salpingectomy will likely damage the mother's fertility.
I mean, if you don't have any understanding of the principle of double effect, this sounds nuts. Even if you do have an understanding of the principle of double effect, it might still sound nuts. You have to sit down and take time to connect all the dots to figure out how we got from here to there, or why it matters that we prefer one option to the other when the end result is a no-longer-in-danger mother and a dead embryo for all of them, and especially why "but the salpingectomy is more dangerous!" isn't a good enough reason to use one of the other methods, considering that the embryo is dead either way.
And yet, this is where double effect, properly understood, gets you. If it isn't obvious, why not head over to Jennifer's blog and see if you can make the connections between her bathtub assailant and the unfortunate ectopic pregnancy problem? If nothing else, the exercise illustrates why it's important for ordinary Catholics who desire to follow Church teachings -- whether they understand them or not -- to be confident that their local Catholic hospital faithfully follows it, and why the bishops have to guard that confidence even if it means getting bad press.
(UPDATE. Edited slightly to avoid implying that salpingostomy is definitively considered illicit. See first comment.)