Wednesday, February 16, 2011

Lying, part 1

I have at least one friend who believes it is never justified to tell a lie. Hmm.

I have two basic problems with this, and one rather more complicated problem. First, there is a difference between speaking the truth and communicating the truth. Second, lying is often necessary to keep one's private information private (which I feel is generally my right). Third, people don't necessarily want the truth (or the truth might not be in their interest, whether or not they are aware of it). I will cover these in 3 separate posts; I think there's some worthwhile discussion to be had here, regardless of whether you would go as far as my friend on this matter.

Before diving in, here's a general take-away I'm hoping to get across: Whether lying is good or bad is not a one-party question that should be answered in a vacuum. It really matters what everyone else is doing. It matters what equilibrium we're in, because that determines how are actions are interpreted, and the interpretation is what we should really care about.

Lying, Part 1.

For the first point, assume we're in a context where we want to get the truth across. That is, we want to communicate the truth. Then should we feel compelled to speak the truth? The two questions that arise are:
  1. Can communicating the truth can actually differ from speaking the truth?
  2. If they do indeed differ, is it really fair to assume our goal is to communicate the truth, or might we justifiably care about speaking the truth instead?
The answer to #2 seems pretty clear to me (but speak up if you disagree!): If you are going to swear allegiance to the truth, it would strike me as oddly disingenuous to care about the act of saying true words rather than the act of communicating true the same way that you might frown on "implying" a falsity without technically lying. Who cares what the words literally say? Words exist for exactly one reason, and that is to that's the standard by which I am inclined to judge them.

On the other hand, perhaps it isn't immediately obvious that speaking and communicating the truth can even differ, but a simple example should make clear that a lie can easily move us closer to communicating the truth. [Note: I will not be discussing technicalities, such as the trivial case where a lie communicates the truth because it is true under colloquial understanding but technically false when taken extremely literally. I am interested in the case where one person is unambiguously lied to in the colloquial sense, and nevertheless ends up closer to understanding the truth, by some reasonable measure].

So, let's say you did your homework, but on the way to school, an improbable chain of events transpired during which it was stolen. When the teacher asks where your homework is, do you tell her about the neighbor's escaped pet monkey who attacked you and grabbed it out of your hands, or do you just tell her you "lost it"? Well, do you want her to think that you didn't do the homework and have no respect for her intelligence, or just that you didn't do the homework? (Because, like it or not, that's how your stories will be respectively interpreted). The choice is yours; for my part, I will choose the option that actually communicates something closer to the truth.

The point is this: You want the teacher to know the truth? Tough. Speak the truth if you like, but given that we aren't in a world where everyone always speaks the truth, whatever you say is simply a piece of data that goes into her likelihood function to update her posterior probabilities over what's true. That's all the control you have over her grasp of the truth. And if you really care about the truth itself, rather than simply the act of saying true words, then you should try to say words that will move her closer to the truth.
[Flag: The above says that in our current equilibrium, a lie may make us better off; it does not necessarily say we're better off than we would be in an equilibrium where nobody lies. With respect to this point, it can make sense that a religion (or some other set of social norms) might try to compel everyone to honesty. Nevertheless, it is our job to decide the best course of action given that they did not fully succeed, given that we live in a world where honesty is not ubiquitous, given that by our own actions we cannot move society to the desired equilibrium. If this point bothers you, I am happy to entertain discussion! In any case though, I suspect the next paragraph is fatal to honesty-as-unqualified-virtue, even in a world with total honesty.]
Furthermore, even if someone completely trusts you, you still have to worry about correlation between things you do and don't mention. Pretty much anything you can say is going to lead them to update their beliefs on the likelihood of any number of related things, possibly in the wrong direction to ill effect. For instance, you may say (truthfully) "I'm from neighborhood X" and that may cause them to revise their impression of you in a number of erroneous ways. Depending on the circumstances, it may simply be better to say something else. Alternatively you could say, "I'm from neighborhood X, but I don't have characteristic A, or B, or C, or D, or...." But that may be prohibitively costly, or altogether impossible.


As I have said, I think the goal of words should be communication. And if that is the goal, then adding an additional constraint can only inhibit your pursuit of that goal. In trying to get closest to communicating the truth, restricting yourself to literally true sentences can only make your solution worse. Why does the best route to understanding a truth always have to be made up of actual true sentences?

Another moral is this: A rule like "Never tell a lie" seems attractive because it's unambiguous and easy to follow. But in my experience, unambiguous and easy-to-follow rules tend to fall apart as soon as you ask, "Wait, what should I really care about?" Reality is generally far too multidimensional and messy to admit such a cut-and-dry rule. Once we recognize that communication is what matters, we are forced to acknowledge that the corresponding rule, "Never communicate a falsity," is not followable! There are tradeoffs. Just about anything you do will, in reality, move people closer to the truth along some dimensions and farther along others. So in deciding what to do, it becomes necessary to quantify these movements in some way, to weigh them against each other according to some rubric relevant to the situation. In other words, it becomes like any old optimization problem. "Rah rah!" say the economists...that's what decisions are supposed to look like, right?

Finally, so long as we're on this topic, note that the above homework example, in its simple absurdity, communicates a truth very efficiently. Economists and mathematicians understand this; that's why they're okay with their simple models and their stories about blue-eyed islanders. To respond by insisting on "realism" (as many instinctively and indiscriminately do) is to forego an easy opportunity to connect with some truth, some distilled feature of reality. When literal truth is expensive or confusing or otherwise poor at communicating truth, abandon it. But why discard a literal lie that successfully communicates truth, simply on the basis that it doesn't speak the truth?


  1. (1) I am so glad you are blogging, Xan.

    (2) You’ve convinced me: Sometimes lying is justified. (Nice example, by the way.)

    (3) I get that “never communicate a falsity” is not followable, but would you have objections to “never *try* to communicate a falsity”?

  2. "...and the interpretation is what we should really care about." I think this needs some justifying and/or qualifying.

    I don't think telling the literal truth is always necessary or advisable. In the Bible we even see God commanding Abraham to be deceptive regarding his relationship with Sarah. But I would say that, for most of us, the net marginal benefit from honesty is positive.

    Continuing with your homework example, suppose the teacher later finds out about the extraordinary circumstances under which the student lost his homework. If the student had told the truth, despite the fact that he knew it would likely be disbelieved, this would increase his reputation for honesty (which is good for him). It seems to me that maintaining a reputation for honesty is very important, and perhaps one of the primary reasons people are as honest as they are.

    Also, I think some honesty advocates would argue that the very act of speaking an untruth damages ones character.

    Lastly, in world where much of our communication is recorded, it makes sense to me to care about both the words you are saying and how your intended audience will interpret them. You may find yourself defending those words (not their intended meaning) to an unintended audience someday!

    I admit that none of these points necessarily drive you to a corner solution. After all, I don't think telling the literal truth is always necessary or advisable. But I think that the circumstances under which less than full honesty is advisable are rather exceptional.

  3. Justin,

    (1) me too.

    on point (3), once communicating truth is demoted to "not always possible," we are in tradeoff land and the door is open not just to communicating truth A versus truth B, but also to tradeoffs between communicating truth and entirely different sorts of goals. If you were bound to the singular goal of trying not to communicate a falsity, you might spend a lot of time not speaking, which would probably be suboptimal for a lot of other reasons. It is probably better to just accept communicating truth as one of many sub-objectives in your utility function. In my opinion, it doesn't deserve to be elevated above other things such as "feed oneself." If you have to communicate falsity to keep from starving, you will find no objection here.

    In general I find prescriptions of the form, "Never __" deeply problematic. You certainly can't accommodate too many of them before you run into contradictions.

  4. Ian,

    Thanks for the comment! Please don't interpret this as a general slam on honesty, which overall I think rather highly of. *Reputation* is extremely important in the real world, where many interactions resemble a repeated game.

    "the very act of speaking an untruth damages ones character." Yes, I can imagine people saying that. Don't feel compelled, but if you do want to pursue this, please tell me what you mean by "character." Depending on the semantics, I suspect that either I disagree with this, or I agree but "character" is not something it makes sense to me to care about. It is either a feature of reality or not, and that tends to determine my position.

    Your last point is extremely salient, and actually something I perpetually struggle with. When I write something, I tend to forsake communicative clarity in favor of precision (hence I tend to write on the long side of things). I tend to cover too many bases, perhaps losing a lot of people in the process, but defending against attack by a certain subset of them. In its mildest form, I find myself leaving lots of little 3-word loopholes here and there...

    I don't think I agree with you that "the circumstances under which less than full honesty is advisable are rather exceptional" but maybe that's a conversation to have after the next couple posts. Your statement may be true for the particular subset of circumstances you're considering tho.

  5. I think the "problem" here is expressed with two words in your first sentence: "belief" and "never." Belief is belief; it's a choice. People can and do believe whatever they want. It isn't rational. "Never" is pretty rare in the real world, so believing that anything is never is an emotional choice. To debate it is, well, another choice.

    The subject of lying is simply a value-laden, emotionally charged context for this much more generally applicable concept. Reality rarely conforms well to a model that involves "never" or "always."

  6. Bob,

    Thanks for the comment. You seem to suggest there is little point to this analysis since beliefs are beliefs, unimpeachable objects that need not stand up to the force of reason. (Am I reading you correctly?) And while I don't think moral beliefs are anchored to reality either, I do see them as tied to other beliefs...and that's the angle I am trying to approach "never lie" from. That is, I am *taking as given* my friend's set of beliefs, and saying, "Hey, you believe X and Y. But X and Y are not compatible, here's an example. So which do you really believe?" If my friend actually cares more deeply about X, and if he *wants* his beliefs to be tied together by basic logic (which this friend does), then he *can* come away with his beliefs changed. Whatever the genesis of belief Y (perhaps it is "emotional", as you call it), there is a real chance that it will be affected by this sort of argument, which gives the argument purpose.

    In some sense preferences are arbitrary, but that doesn't mean they can't be changed, and it doesn't mean we can't have a fruitful discussion about how you might like your own preferences to change, even taking your current preferences as *given*. Similarly, it is not a waste of time to reason about morality or beliefs even if your current beliefs are not themselves the product of reason.

  7. Hi, Xan. Thanks for replying. No, I think your thoughts on the value of dishonesty are very interesting and worthwhile. Based on what you've written here, I doubt that we will disagree on much about it. And I realize that your friend's belief that you state up front is probably mostly a device for introducing the topic. My point is that, in many ways (for me) that introduction occludes the real point. Or maybe it supplants your intended point with something that for me looms larger.

    Pure honest communication could be considered a worthy goal, but I think it's one that's impossible to achieve. The meanings of words like "lie" and "justifiable" can easily be nuanced to support whatever value-reality match is desired. And, as you're pointing out, there clearly are situations in which brutal honesty is incompatible with other values.

    So... My point #1 is that the motivation for your treatise is not at all to debate your friend's "belief" but to state clearly why you value dishonesty in specific circumstances. I appreciate the straightforward ownership of one's values.

    My point #2 is that people who choose to fill in the gaps in their knowledge by creating absolute rules by which to live, especially those that include "always" or "never" are probably not paying attention to what goes on in their lives or their minds. It's literally an incredibly simplistic way of being.

    As Lao-Tsu said, "Suppleness and tenderness are concomitants of life. Rigidity and hardness are concomitants of death."

    Thanks for taking the time and thought to express yourself here, Xan. It's all worthwhile.

  8. Hey Bob, thanks for following up.

    Both of your points are well-taken, although in this case I actually am partially motivated by the thought that my particular friend would be susceptible to this line of reasoning. For one thing, he happens to be an economist, and furthermore I have heard him pose the question before: In what situation would it ever make sense to lie? I think he is actually interested in the answer to that question.

    The set of people who would believe in the occasional sensibility of lying, if only the right situation had occurred to them, is nonempty, and that alone could make this worthwhile. But you are correct that that isn't my main motivation for these posts. There are people who haven't taken it as far as my friend but have still taken it *some* distance in the wrong direction, as well as many people who maybe loosely agree but don't necessarily know explicitly why. These people (who presumably far outnumber those like my friend) may appreciate some concrete examples, and come away with a sharper model of the world and what they should care about. Our culture sponsors a particular view of how we *should* think about lying, and it exerts a pull even on people who aren't pulled all the way to the edge.

    By the way I would continue to emphasize things like this: By "lie" I mean what my friend means by "lie." Similarly, "justifiable" is not defined on its own, but for the purposes of this discussion, I am happy to take the meaning that follows from my friend's (most deeply held) moral beliefs. Or more generally, I am asserting not that everyone will necessarily agree on a definition of "justifiable," but that taking most anyone's own definition of "justifiable" as given, the result will follow that lying is not always unjustified.

    (So there isn't actually supposed to be ambiguity in the usage of these terms.)