Why Impractical Knowledge is More Efficient<\/h2>\n
Imagine knowledge is like a tree:<\/p>\n
![\"\"](\"https:\/\/www.scotthyoung.com\/blog\/wp-content\/uploads\/2026\/09\/Tree-practical-advice.jpg\")
<\/figure>\n<\/div>\nAt the base of the tree are principles. These are the things that are least contingent on specific states of the world, and are most generally true. This category includes stuff like F<\/em> = ma<\/em> or the conservation of momentum or energy.<\/p>\n These principles are general, but they\u2019re also insufficient by themselves for a lot of situations you care about. You need to know a lot more than just F<\/em> = ma<\/em> to design a good bridge or rocket ship. So, as we travel up the trunk, we get to branching points. These represent splits in the state of the world.<\/p>\n For example, while it is true that heavier objects and lighter objects fall at the same speed. We have domains where air resistance is practically irrelevant (lead ball vs solid gold ball), and domains where this becomes a noticeable factor (feathers vs rocks).<\/p>\n As you learn more about the specific, concrete situation you\u2019re in, you branch more and more until you finally come to the leaves of the tree.The leaves of the tree are practical advice. They\u2019re the kinds of \u201ctips\u201d you might give someone who doesn\u2019t know much about a particular domain, deep down, and just wants to know what sorts of action they should take. This would be things like, \u201cmake your propeller blades exactly this shape to minimize air resistance.\u201d<\/p>\n Here\u2019s a first observation: there are far more leaves than there are trunks. Each leaf only covers an incredibly narrow subset of possible states of the world, so to reasonably \u201ccover\u201d much of the space of possibilities you need to learn tons and tons of different advice for different cases.<\/p>\n This suggests if you want to maximize your breadth of usefulness, meaning the number of concrete situations advice applies to, you\u2019re better off learning lower down the tree of knowledge, to ideas and knowledge that are less dependent on specifics.<\/p>\n Let\u2019s try this analogy with a few examples. <\/p>\n Consider a goal of getting in shape.<\/strong><\/p>\n The leaves would be a particular workout plan you decide to follow. Further up the branches, would be principles like progressive overload and recovery. Towards the trunk, you\u2019d have more basic ideas like energy metabolism, muscle and cardiac physiology and so on.<\/p>\n Following a specific workout plan is fine, as long as your situation conforms closely enough to the situation being advised. But what if the workout plan was made for a serious athlete in their twenties, whereas you\u2019re 55 and recovering from an injury? Then, the advice itself is unlikely to be applicable, and may even be counterproductive.<\/p>\n \u2028In contrast, the knowledge of more basic principles would still apply, and could steer you to advice on a new branch of the tree of knowledge.<\/p>\n Or consider starting a business.<\/strong><\/p>\n The leaves are particular tactics like \u201cbuy ads on Facebook\u201d or \u201ccold call purchasing managers at mid-sized firms.\u201d Again, if you\u2019re in the domain where this advice applies, perhaps because you\u2019re receiving it from someone in a very similar business, this may be what you need to hear.<\/p>\n \u2028But, if you\u2019re not, chasing these tactics may be counterproductive. Instead, you should focus on ideas further down the trunk. A little further down the tree are basic ideas of entrepreneurship like \u201cproduct-market fit\u201d \u201cminimum viable product\u201d or \u201cmarket research.\u201d And towards the base you have even more basic concepts like \u201csupply and demand.\u201d<\/p>\n Or consider the topic I write most about: effective learning.<\/strong><\/p>\n If you\u2019re studying for an exam, then advice for how to pass your particular exam would be the leaves. Further down the branches are somewhat more general ideas for tackling multiple choice questions or organizing your studying materials. Finally you get to bedrock ideas about learning like the spacing effect or retrieval practice.<\/p>\n The latter are most universal, even if they leave degrees of freedom for how you should actually deal with any particular situation.<\/p>\n There are a few common objections to focusing on principles over practicalities:<\/p>\n First, there\u2019s the objection that principles don\u2019t constrain decision-making enough. <\/strong>That much is true. Rarely does learning a deep principle give you all you need to know to decide the best course of action in a concrete situation. Usually there\u2019s too many other considerations at play.<\/p>\n But, learning principles is still more efficient. It\u2019s just that sometimes it needs to be supplemented with more knowledge to get you to the correct answer.<\/p>\n To continue our arboreal analogy, imagine you\u2019re trying to find a squirrel in a tree. Saying \u201che\u2019s on the third branch from the right\u201d doesn\u2019t tell you exactly where he\u2019s located, but it does give you a starting place to look. In contrast, only knowing whether or not he is on a particular leaf is only helpful if he actually is on that leaf\u2014in most cases, that information doesn\u2019t limit your search very much. Directly applicable advice is only helpful if it actually describes the situation you\u2019re in.<\/p>\n Second, there\u2019s the objection that the principles don\u2019t actually describe the world. <\/strong>The theoretician has come up with an elegant-sounding principle that doesn\u2019t actually give useful advice in the domain of practical concern.<\/p>\n This is an issue, but it\u2019s more typically the case that the principles are still largely undiscovered or don\u2019t satisfactorily constrain the problem. This is like a map of knowledge where we can see a bunch of leaves, but don\u2019t really know the location of all the branches underneath the canopy. We guess at some, but maybe those guesses are wrong.<\/p>\n This is correct, as far as it goes. In domains where principles strongly determine the practical advice, such as physics and engineering, there\u2019s a strong rationale for learning the fundamental principles. In domains where principles only weakly determine the practical advice, say entrepreneurship or second language learning, then they\u2019re still worth learning, but they\u2019ll have to be supplemented with a lot more situation-specific advice.<\/p>\n But this isn\u2019t really a negation of the idea that principles are more efficient. It\u2019s simply the case that sometimes we don\u2019t know what the principles are, and so only practical advice can be generated.<\/p>\n Finally, there\u2019s the possibility that figuring things out from fundamental principles is intractable, and so we have to go by practical advice<\/strong>. \u2028\u2028Continuing our analogy, the closer to the trunk you go, the more mental work needs to be done to figure out where the branch points are and where the leaves end up.<\/p>\n \u2028This is also a fair critique, and it\u2019s one reason why we have hierarchical domains in the first place and everything isn\u2019t just quantum mechanics. But this simply means that for really complicated domains, we occasionally need more knowledge from higher up the tree to make the principles useful. But because the span of the principles is broad, they still tend to be more efficient for learning.<\/p>\n Applying this idea reflexively, we can see the idea of \u201clearning principles is more efficient than practical advice\u201d is itself a deeper principle. So, what are the practical consequences?<\/p>\n Consider the raft of practical advice book on topics like productivity, diet or personal finance. How many of these are just leaves? The new \u201cfat-busting\u201d diet plan that will have you losing fifteen pounds in fifteen days. The specific habits your favorite author uses to write books. The budget plan for retiring by 45. And so on.<\/p>\n If you were only going to read one book, perhaps one practical book would be best. After all, the fundamental principles don\u2019t sufficiently constrain advice, so, yes, they won\u2019t give you something to do. Whereas if you buy one of these books, maybe you happen to be in the exact situation the author describes and thus can benefit from their advice?<\/p>\n But if you\u2019re going to read more than one book, don\u2019t start there. If the trunk of the tree is largely within an academic field, such as nutrition or psychology, read a textbook. If the trunk of the tree is within the scope of some professional practice, read a book that aims to give the basic information in an unbiased way. \u201cFor Dummies\u201d and other general readers are good examples.<\/p>\n Even more generally, make it a personal maxim to try to read as much as possible of the \u201ctrunks\u201d of various domains of knowledge. Then, when you do have a practical problem that requires detailed knowledge of the leaves, you may still have some work to do, but at least some of the most important learning will already have been completed.<\/p>\n \n","protected":false},"excerpt":{"rendered":" Most readers prefer useful advice to abstract theory. They shouldn’t.<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":"","_links_to":"","_links_to_target":""},"categories":[3],"tags":[],"class_list":["post-18674","post","type-post","status-publish","format-standard","category-personal-development","entry"],"acf":[],"yoast_head":"\nSome Examples<\/h2>\n
Dealing with Some Objections<\/h2>\n
Applications for Real Life<\/h2>\n