Final answer:
The 'magical number 7' theory by George Miller is about the capacity of short-term memory, suggesting an average person can hold about 7 items (plus or minus 2) in their short-term memory. Later research indicates this number might be around 4 plus or minus 1.
Step-by-step explanation:
The 'magical number 7' theory refers to a concept in cognitive psychology related to the capacity of short-term memory. It was proposed by psychologist George Miller in 1956 after reviewing various studies on memory.
According to his findings, the average person is able to hold about 7 items (plus or minus 2) in their short-term memory. This is sometimes expressed as the "magic number" 7 plus or minus 2. However, later research by Nelson Cowan in 2010 suggests that the true capacity of working memory might be closer to 4 plus or minus 1.
It's also notable that recall tends to be better for numbers than for letters and for information that is heard rather than seen. Despite the impressive nature of our memory systems, most people experience memory failures and can benefit from using memory-enhancing strategies like rehearsal.
This concept does not relate specifically to education topics such as ideal class size, stages of learning, or notions of luck in academia, but rather to the underlying cognitive abilities that can impact learning and information retention.