Spaced repetition, a learning technique that schedules reviews at increasing intervals, can theoretically lead to near-perfect, long-term retention. By strategically timing repetitions just before forgetting occurs, the memory trace is strengthened, making recall progressively easier and extending the retention period indefinitely. The article argues against the common misconception of a "forgetting curve" with inevitable decay, proposing instead a model where each successful recall flattens the curve and increases the time until the next necessary review. This allows for efficient long-term learning by minimizing the number of reviews required to maintain information in memory, effectively making "infinite recall" achievable.
Cab numbers, also known as Ramanujan-Hardy numbers, are positive integers that can be expressed as the sum of two positive cubes in two different ways. The smallest such number is 1729, which is 1³ + 12³ and also 9³ + 10³. The post explores these numbers, providing a formula for generating them and listing the first few examples. It delves into the mathematical underpinnings of these intriguing numbers, discussing their connection to elliptic curves and highlighting the contributions of Srinivasa Ramanujan in identifying their unique property. The author also explores a related concept: numbers expressible as the sum of two cubes in three different ways, offering formulas and examples for these less-common numerical curiosities.
Hacker News users discuss the surprising mathematical properties of "cab numbers" (integers expressible as the sum of two positive cubes in two different ways), focusing on Ramanujan's famous encounter with the number 1729. Several commenters delve into the history and related mathematical concepts, including taxicab numbers of higher order and the significance of 1729 in number theory. Some explore the computational aspects of finding these numbers, referencing algorithms and code examples. Others share anecdotes about Ramanujan and discuss the inherent beauty and elegance of such mathematical discoveries. A few commenters also provide links to further reading on related topics like Fermat's Last Theorem and the sum of cubes problem.
Summary of Comments ( 121 )
https://news.ycombinator.com/item?id=42908041
Hacker News users discussed the effectiveness and practicality of spaced repetition, referencing personal experiences and variations in implementation. Some commenters highlighted the importance of understanding the underlying cognitive science, advocating for adjusting repetition schedules based on individual needs rather than blindly following algorithms. Others debated the difference between recognition and recall, and the article's conflation of the two. A few pointed out potential downsides of spaced repetition, such as the time commitment required and the possibility of over-optimizing for memorization at the expense of deeper understanding. Several users shared their preferred spaced repetition software and techniques.
The Hacker News post "Spaced repetition can allow for infinite recall (2022)" linking to an article on efavdb.com has generated several comments discussing the merits and nuances of spaced repetition as a learning technique.
Several commenters agree with the premise, sharing their positive experiences with spaced repetition systems (SRS) like Anki. They highlight the effectiveness of SRS for memorizing vast amounts of information, ranging from vocabulary and medical facts to programming languages and historical dates. One commenter points out the importance of creating high-quality flashcards with clear context and meaningful connections to maximize retention. Another emphasizes the psychological benefit of the "investment" made in crafting good flashcards, leading to a stronger commitment to the learning process. The ease of integrating spaced repetition into daily routines is also mentioned as a significant advantage.
However, some commenters express more nuanced perspectives. One individual argues that while spaced repetition excels at rote memorization, it might not be as effective for deeper understanding or the ability to apply knowledge creatively. They suggest that other learning methods might be more suitable for these goals. This point sparks a discussion about the difference between remembering and understanding, with some arguing that robust memorization forms a solid foundation for deeper comprehension.
Another commenter raises the issue of the time commitment required for spaced repetition, acknowledging its effectiveness but questioning its practicality for individuals with limited time or those who struggle with maintaining consistent study habits. They propose alternative learning strategies that might be less demanding but potentially less powerful for long-term retention.
A few commenters delve into the technical aspects of spaced repetition algorithms, discussing the importance of parameters like the forgetting curve and the spacing intervals. They also mention the potential for customizing these parameters to optimize individual learning styles and preferences.
One commenter introduces the concept of "elaborative encoding," which involves actively relating new information to existing knowledge to enhance memorization. They suggest combining spaced repetition with elaborative encoding techniques for optimal results.
Finally, some comments address the limitations of spaced repetition. One commenter points out that while it can facilitate recall, it doesn't necessarily guarantee comprehension or the ability to use the recalled information effectively. Another raises the possibility of "illusory fluency," where the ease of recall within the SRS environment might not translate to real-world application.
In summary, the comments on the Hacker News post reflect a generally positive view of spaced repetition as a powerful learning tool, particularly for memorization. However, they also acknowledge its limitations and emphasize the importance of considering individual learning styles, time constraints, and the specific learning goals when deciding whether to adopt this technique. The discussion highlights the nuances of spaced repetition and encourages a balanced approach to learning that incorporates various strategies beyond rote memorization.