[Estimated time: 11 mins]
As I explained in my summary of The Art of Logic, I generally enjoyed the book except for the examples and the tone, which came off self-righteous at times.
In this post, I’ll try to explain why this book has such an awful Goodreads rating (less than 3.5 right now), and then suggest that you ignore that and read it anyway.
The two main problems with The Art of Logic were:
- the examples were poorly chosen; and
- Cheng’s lack of self-awareness.
Poorly chosen examples
Cheng’s examples are poorly chosen in at least two ways. The first is that she oversimplifies difficult social and political problems. The second is that the chosen examples are rather unbalanced.
Oversimplified examples
So I understand that a book like this has to use relatively simple examples for readability. But you shouldn’t pick examples that will raise very complex social issues if you can’t do them justice!
If Cheng had really wanted to use these examples, she should have focused on just one or two complex examples throughout the book and used them to show all aspects of logic.
For example, to show how to build up chains of logical implication, Cheng argues:
1. If you don’t stand up for minorities being harassed then you are letting bigotry flourish.
2. If you let bigotry flourish you are complicit with bigotry.
3. If you are complicit with something bad then you are almost as bad as it.
4. Therefore if you don’t stand up for minorities being harassed you are almost as bad as a bigot.
She then writes:
It is important to note that the conclusion is true if you don’t stand up for minorities, but the implication is true whether or not you stand up for minorities. … My statement is still true although you personally are not actually anywhere close to being a bigot.
However, each step of Cheng’s example is highly debatable in ways that she does not acknowledge, or even hint at. If she’d insisted on using this example, she could have used it to demonstrate:
- How differing definitions and assumptions can cause people to talk past each other. What does “stand up for minorities” mean? What counts as “almost as bad”? Reasonable and logical people can hold very different views on these.
- Grey areas. Cheng does not account for the personal risk (including any social costs) involved in standing up for minorities. I could see how someone would be “complicit with bigotry” if they refused to stand up against a bigot when it involved zero personal risk (including social risk). But I wouldn’t say they were “complicit with bigotry” if standing up to the bigot would cost them their life. Disagreements may therefore come down to how much personal risk we can expect people to take, which is a grey area.
- Causation. Cheng’s reasoning seems to assume that “standing up for minorities” is necessary and sufficient to stop bigotry from flourishing. But perhaps someone doesn’t stand up for minorities because they think that doing so would be futile and may even backfire. Alternatively, they might think other ways of stopping bigotry—say, through education—would be more effective.
- Abstraction and analogies. At the highest level of abstraction, Cheng is arguing that not doing something bad is “almost as bad” as doing that thing. But at that level, the statement is clearly absurd. There are wars, atrocities and countless crimes occurring around the world right now that I am not stopping. But I don’t think that means I am almost as bad as those criminals. Presumably, Cheng would argue for a lower level of abstraction—perhaps where something bad is in happening front of me and within my power to stop. This then brings us back to the issues of grey areas and causation.
If Cheng had taken this approach, she could’ve brought nuance to a complex issue and perhaps even changed some people’s minds. Unfortunately, she does exactly what she criticises here—choosing to say “something with impact” rather than “something true”:
Achieving the illuminating precision sometimes takes longer – more thought, more words of explanation, more groundwork – and this is often unacceptable in today’s world of soundbites, memes, and so-called mic-drops. It turns out that saying something with impact is often more important than saying something true.
Unbalanced
Besides being oversimplified, the examples Cheng picks also consistently favour the left side of the political spectrum. When giving examples of unstated assumptions in arguments, she listed:
- “[A]rguments about benefits, when some people tacitly assume that people are only poor if they are too lazy to work hard.”
- “[A]rguments about abortion when some people assume that unwanted pregnancies only occur if people are promiscuous.”
- “[A]rguments about clinical depression when people assume that depression is caused by circumstances and therefore there is no reason a successful person should be depressed.”
These are all valid examples of unstated assumptions that contribute to arguments. I’m also sure some people do hold all of these. But she really could’ve picked a more balanced mix.
For example, she could’ve pointed out that some people assume that those who don’t support raising the minimum wage don’t want to help the poor, rather than because they think it’s an inefficient or ineffective way of helping the poor. Or that some people assume organic farming is better for the environment when the evidence suggests it’s actually worse.
There are plenty of erroneous assumptions on both sides of virtually all political issues.
As it stands, I think Cheng’s book alienates readers on both sides of the aisle. Those on the right will likely get irked by the way in which she straw-mans their positions. Those on the left may get irked by Cheng herself coming off like a caricature of a self-righteous Liberal.
Moreover, the book’s title The Art of Logic is so anodyne that I think it’s rather sneaky to put politically charged topics in there at all. Like my Criticisms of Economics: The User’s Guide, I expected more neutrality based on its title.
Lack of self-awareness
Cheng isn’t completely lacking in self-awareness. She acknowledges that her positions rely on axioms that are not held up by logic. She also recognises that many differences are differences of degree—that there are shades of grey and people may choose to draw the line in different places, or abstract a situation in different ways. As such, she recognises that two people can disagree without either being illogical.
But I still get the sense throughout the book that she still thinks she is “right” on many of these issues that come down to different axioms. For example:
In the process of writing this book and thinking through these arguments very carefully, stripping away layer upon layer to find further abstractions and logical points of view, I have realised how many of these arguments come down to tensions between the idea of individuals and the idea of groups. This applies to the idea of individual vs group responsibility, the extent to which everyone should look after themselves or whether there should be group care. It applies to whether people think a group’s treatment by society has any bearing on an individual’s. This may go back to a difference in basic personal axioms, in which case we will need to think about how to persuade someone to change their axioms. [Emphasis added.]
And:
Once we have uncovered someone’s axioms that are at the root of a disagreement, we can start thinking about how to change them. If they are deeply rooted it can be hard, but it could be done by experience, meeting people, education, empathy, but in all cases by engaging them emotionally. [Emphasis added.]
These quotes show a strong “soldier mindset”, where her goal is to persuade others of her view, rather than “a scout mindset” where her goal is to find the truth and she’s open to the possibility that her axioms may be wrong.
Indeed, I think one of her axioms—caring about false negatives more than false positives—is wrong.
Example: Caring more about “false negatives”
Cheng mentions several times that she has an axiom of caring more about “false negatives” than “false positives”. She explains how this applies in variety of situations, from the provision of social services to dealing with jetlag to cancer screening to sexual harassment accusations.
This axiom seems rather arbitrary. The costs of false negatives and false positives will differ in different cases, so it doesn’t make sense care more about false negatives (or false positives) in general.
Cheng’s reference to sexual harassment accusations is particularly troubling. In many countries, civil cases are decided on the “balance of probabilities”, which treats false negatives and false positives equally. Criminal cases require a higher standard. To convict someone, the prosecution must show that the defendant is guilty “beyond reasonable doubt”. So the criminal system is more concerned about avoiding false positives (convicting innocents) than false negatives (letting wrongdoers go free). Cheng’s aversion to false negatives implies that she supports a standard even lower than “balance of probabilities”—perhaps something like “reasonably possible” would suffice!
Another example where Cheng’s axiom could be problematic is in warfare. A false positive means you attack innocent bystanders while a false negative means you’ll fail to attack a hostile target. A general preference for false positives would mean you should always err on the side of attacking.
Now, I don’t know if Cheng would actually endorse these views. I suspect she doesn’t. But they highlight areas where her axiom would lead to views that are highly unorthodox.
Even in the social services case, where a false negative means we don’t help those who need it and a false positive means we help someone who doesn’t need it, I’m not sure the axiom is justified. With resource like money, every false positive is a false negative. Money spent helping out someone who doesn’t need it is money that could’ve been spent helping someone who does.1This doesn’t mean I think we should try to carefully target everything either, because targeting involves administrative costs and those are not always worth it. My point is just that a blanket preference for false negatives or positives does not make sense, and it should instead be considered on an issue-by-issue basis.
To be fair to Cheng, she admits that axioms are core beliefs that you don’t try to justify by logic, so she’s not necessarily arguing that you should care more about false negatives too. But given her comments above about persuading others to change their axioms, I think it’s fair to call Cheng out on hers.
Throughout the book, I got the impression that Cheng simply hasn’t been exposed to serious, well-informed challenges to her views. That might explain why so many of her examples are oversimplified—she may not realise how complex the issues are.
Conclusion
Overall, Cheng’s writing came across a bit tone-deaf. Perhaps she simply didn’t care how she’d come across, but I don’t see why she’d want to unnecessarily alienate a bunch of readers. Besides, I think balanced approaches are generally more persuasive than zealous ones.
It wasn’t all bad. In a few parts, Cheng did show some self-awareness and open-mindedness. I also agreed with the overall message of the book. Cheng made some excellent points about the limits of logic and listening for the feelings behind someone’s emotional outburst instead of nitpicking their logic.
Unfortunately, Cheng’s not very good at practising what she preaches. It’s really a shame because if you can ignore the problems above, The Art of Logic is well worth reading. I’ve certainly found it helpful in clarifying my thinking, and there are plenty of people I’d like to recommend it to (in a nice way). But Cheng’s political views are very distracting, and people could assume from my recommendation that I share those views. So any recommendation will have to come with some careful caveats.
Let me know what you think of my criticisms of The Art of Logic in the comments below!
If you enjoyed this post, you may also like:
- Book Summary: The Scout Mindset by Julia Galef — this book talks about how we should approach arguments as a “scout” motivated to find out the truth, instead of as “soldiers” motivated to defend our views
- Podcast Summary (EconTalk): David McRaney on How Minds Change — this talks more about how you can’t change people’s minds by simply giving them more facts
- Book Summary: Calling Bullshit by Carl Bergstrom and Jevin West
- 1This doesn’t mean I think we should try to carefully target everything either, because targeting involves administrative costs and those are not always worth it. My point is just that a blanket preference for false negatives or positives does not make sense, and it should instead be considered on an issue-by-issue basis.