A computer can remember billions or trillions of facts perfectly, while humans struggle to remember a handful of phone numbers.

Judge as of January 2001. The claim has two parts: (a) computers could store and retrieve billions or more discrete facts without error; (b) humans have very limited capacity for recalling arbitrary items, such as a handful of phone numbers. True: 2001 databases or storage stored and retrieved at least billions of records reliably, and memory research shows human short-term or arbitrary recall is limited to a few items (for example about 7 digits). Mostly true: (a) holds and (b) is a rhetorical exaggeration of a real, documented human memory limitation. Mixed: one part holds and the other is clearly wrong. Mostly false: both parts are substantially overstated. False: computers in 2001 could not store billions of facts reliably, and humans do not have notably limited recall.

Set before the research began.

1. E1 The Magical Number Seven, Plus or Minus Two George A. Miller, Psychological Review (hosted copy at University of Texas Labs) · 1956

   “Begin with the observed fact that people can repeat back eight decimal digits, but only nine binary digits.”

2. E2 The Magical Number Seven, Plus or Minus Two George A. Miller, Psychological Review (hosted copy at University of Texas Labs) · 1956

   “For example, decimal digits are worth 3.3 bits apiece. We can recall about seven of them, for a total of 23 bits of information.”

3. E3 The magical number 4 in short-term memory: A reconsideration of mental storage capacity | Behavioral and Brain Sciences | Cambridge Core Cambridge University Press (Behavioral and Brain Sciences) · 30 October 2001

   “Miller (1956) summarized evidence that people can remember about seven chunks in short-term memory (STM) tasks. However, that number was meant more as a rough estimate and a rhetorical device than as a real capacity limit.”

4. E4 The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information Psychological Review (George A. Miller, Harvard University); hosted at labs.la.utexas.edu · 1956

   “Begin with the observed fact that people can repeat back eight decimal digits, but only nine binary digits.”

5. E5 The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information Psychological Review (George A. Miller, Harvard University); hosted at labs.la.utexas.edu · 1956

   “On the basis of the present evidence it seems safe to say that we possess a finite and rather small capacity for making such unidimensional judgments”

6. E6 Computer - Memory, Storage, Processing | Britannica Encyclopedia Britannica · 16 September 2026

   “In 2001 DRAM could be purchased for less than $0.25 per megabyte. This vast decline in cost made possible graphical user interfaces (GUIs), the display fonts that word processors use, and the manipulation and visualization of large masses of data by scientific computers.”

7. E7 Survey: Big Databases Just Keep Getting Bigger | InformationWeek InformationWeek · 26 January 2001

   “SBC's 10.5-terabyte data warehouse running on an NCR Corp. Teradata system contains marketing, finance, and network infrastructure data.”

8. E8 Google index release highlights web trends ITPro · 2 October 2008

   “But the Google 2001 index does contain some 1.3 billion web pages that highlight a number of trends in the growth of online content.”

For part (a), E8 reports that Google's 2001 index held about 1.3 billion web pages. E7, dated January 2001, describes a 10.5-terabyte data warehouse in operation. Together these indicate that systems of the time stored and retrieved records on the order of billions. For part (b), Miller [E1, E2, E4] reports that people can repeat back about seven or eight decimal digits, [E5] describes a finite and rather small capacity for unidimensional judgments, and [E3] calls seven a rough estimate; this is a real limit, but 'hard pressed to remember a handful of phone numbers' is a rhetorical stretch, since these studies describe short-term span rather than long-term memory.