p 81 begins chapter 2 by saying "Darwinian evolution has made us rational." A bit later:
Cognitive psychology has shown that children already have an intuitive grasp of the world.This is an appeal to authority. Worse, it's also unsourced. The purpose of appeals to authority is to justify ideas; they are a justificationist error. They do not serve as good criticisms or explanations, which are the tools of learning.
One of the propositions it's used to support/justify is:
[Children] also have the capability of forming hypothesesThere's no reason to appeal to authority for this claim. It can be argued for in a short, Popperian way. Children learn things. We know this because if you wait a while you'll find they know a bunch of stuff they didn't know before. And how does learning work? By conjecture and refutation. So the implication is that children can conjecture (aka form hypotheses). And, by the way, they can also think of criticisms.
This argument could be evaluated by the reader instead of just irrationally accepted (how are you supposed to correct errors in the propositions you accept without knowing the reasoning for them?). I think this argument is an important part of child psychology and more generally that using epistemology is crucial to understanding how people think, but the discussion in the book has a different approach.
If a child sees a cow give birth to a live calf, the child will be surprised if told the next one will lay eggs. Children are born with a categorizing disposition that places animals into natural exclusive classes, all the members of which are assumed to have the same characteristics. This is their intuitive natural history.This is pretty much advocacy of induction and non-general-purpose thinking (Popperian conjecture and refutation is general purpose, this is something else). It claims children observe stuff and generalize it and then are surprised if their (inductive) generalizations turn out false. And the stuff about categorizing sounds like induction too, it doesn't say anything about conjecturing what categories will solve problems and criticizing one's categories until they are useful, or other Popperian stuff.
Next, in a book about how everyone is rational, we're told about how children will "automatically assume" things which is the epitome of irrationality (since automatic assumptions is a method of thinking that doesn't involve error correction or criticism, or even any opportunity for choice or thinking).
p 85 tells us:
This approach [denial of universality of human thinking; modular approach] fits well with what psychologists have found. Our reasoning abilities are domain-specific and have their own biases and limitations.This contradictions Popper's general purpose explanation of how we create knowledge (by conjectures and refutations). And it's an appeal to the authority of unnamed psychologists. And it's unsourced.
I get that the modular approach is required for evolutionary psychology (because different variants of genes could make the modules be built in different ways, with different biases), but this stuff is all false.
Jerry Fodor (1983) was the first to conjecture that the mind has a collection of special-purpose machines.I have a very hard time believing no one ever thought of that idea before 1983. No argument that he was the first is provided, apparently I'm just supposed to accept it on authority.
The book does have some arguments. Like an example: people who open their eyes "can't help but see a stable three-dimensional environment". I don't think that's actually true -- sometimes I tune out and don't look at the world around me even though my eyes are open. Further, the test subjects are all adults or at least people who know how to communicate, so assuming it applies to all people is unwarranted. Nor do I think if everyone had this experience would that prove it was built into our brains -- we could all learn this approach, much like basically all Americans learn to spell "cat" the same way. Arguing something is common is not a proof that it isn't learned. I don't see anything surprising about convergence on some truths about vision and knowledge about how to see the world being widespread in our culture and reliably passed on to children, so this example fails to impress me.
Backing up, the arguments for the modular approach do not address my arguments against it. They don't address the clash with the Popperian conjectures-and-refutations approach, nor the arguments in David Deutsch's universality arguments in his book The Beginning of Infinity. And more generally, I don't think the book shows any understanding of what it would take to imply specialized brain modules as the only explanation and rule out all alternatives, so it never provides successful arguments that can actually refute all the rival ideas. Since the arguments I find compelling are not addressed, Percival fails to persuade me. Consequently I'm skipping the rest of chapter 2.
Chapter 3 (p 169) is titled "Does Emotion Cloud Our Reason?" and will presumably argue for "no", which I agree with. This sounds more interesting.
But the first sentence of the chapter treats "irrational" as being "insulated against all criticism". But irrationally is normally (perhaps always) partial. It's not all or nothing. We can be better or worse at correcting errors (more or less rational). No one is perfect. Percival also then immediately asks if emotion-based irrationality would make ideologies spread better. This topic comes from chapter 1.
p 169 says
I grant that intense emotion engendered by an ideology may impair the appreciation of critical argument, but I insist that argument is always relevant because our emotions are under the control of our theory of the world and our place in it.I agree. Good point.
I would add William Godwin's argument: even when people are in the most emotional, passionate situations, such as in the middle of intense sex, or whatever other scenario you want to bring up -- at a moving Church service, immensely enjoying getting married, mourning at a funeral, excited by a sports game, extremely angry, etc -- they will promptly snap out of it and put the emotion aside if presented with something more important (in their own judgment) than what they are doing. Like if a terrorist shows up and points a gun at them, they will forget about the wedding or prayer or football game or whatever, and pay attention to the threat to their life. Emotions can be abruptly dismissed when people want strongly enough to focus on something else. And actually emotional states are pretty fragile which is why people having sex will seek privacy and put lots of effort into preventing anything from "ruining the mood".
Really angry people have also been observed to abruptly change to apologetic when they are told some simple fact they hadn't known before and it puts them in the wrong. This refutes the concept that we are slaves to emotion. Certainly sometimes you correct an angry person and he stays angry, but the point is people *can* resist their anger, not that they have to. They can choose to live badly. That people do both things shows that they have the choice.
p 170-171 presents an argument by Pareto which blatantly assumes justificationism as a premise and thus goes wrong. It's really a non-sequitur. And then there is an assertion that that irrational faith can only be based on feelings, which is given as the conclusion of an argument but is actually just a premise written at the end and isn't argued for in any way previously. Percival doesn't point these things out though, I don't know why.
Psychological research, on non-human animals at least, shows that the range of conditioned responses that can be established depends on the specifies of animal.More unsourced appeal to authority. This also assumes without argument that animals have psychology, a proposition I reject on primarily philosophical grounds (so even if I were impressed by appeals to scientific authority, that would miss the point!).
This style is common throughout, e.g. p 180
Experimental research into emotion suggests that...Worse, we're then told, p 180
Everyone agrees that...Then, p 180
Now research seems to show that...There is a section heading, p 180, which reads, "Evidence From Psychology". Then we are told things like "research ... suggests that [stuff]". But evidence does not suggest anything, it is used in criticism, not to establish any positive ideas. So this is non-Popperian.
Then we get, p 180
More recently, Schachter and Singer tested the theory that both cognition and physiological arousal were necessary for a genuine experience of emotion.This is scientism. It is the purported application of scientific method to reach conclusions outside the domain of science. Supposedly they are research scientists doing scientific tests to figure stuff out. But that isn't what's going on. The meaning and proper way to think about "genuine experience of emotion" is a philosophical issue. Genuineness is not an issue open to scientific research, except perhaps after having some philosophical ideas about it, which, depending on what they say, could then be open to some kind of scientific investigation.
You also cannot establish what is necessary for emotion from a handful of examples that you test. A single example could refute that X is necessary by observing emotion in the presence of Y but no X. But how can any finite number of tests establish that X is required for genuine emotional experience? Just because you invoke emotions 500 different ways, all with X, and you try to invoke them 50,000 other ways without X and fail every time, simply does not logically imply that X is necessary to emotion. So the project is utterly incapable of reaching the conclusion it purports to reach. And it has failed -- like bad science often does -- due to philosophical issues.