Defining a Bubble Precisely

In this episode of Run the Numbers, CJ sits down with financial historian and PayPal Mafia member Aman Varejee to explore the recurring patterns behind economic bubbles. Drawing on research from his upcoming book “A Brief History of Financial Bubbles”, Aman explains what defines a bubble, the psychology that fuels speculative manias, and why major technological shifts—from railways to the internet to AI—often coincide with periods of extreme market speculation.

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LINKS: 

Mostly Talent: https://mostlymetrics.typeform.com/to/cLTxtAsN

Aman: https://www.linkedin.com/in/aman-verjee/

https://practicalvc.com/

Aman’s book: https://bigbubbletrouble.com/

CJ: https://www.linkedin.com/in/cj-gustafson-13140948/

Mostly metrics: https://www.mostlymetrics.com

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TIMESTAMPS:

0:00 Preview and intro

1:38 Welcome and guest intro

3:48 Defining a bubble

6:03 Cognitive biases behind bubbles

10:27 Sponsors — RightRev | Rillet | Tabs

13:56 Do bubbles produce breakthroughs?

14:35 Dot-com bubble — winners and losers

16:00 UK railway bubble

21:24 Bubble warning signs

25:30 Sponsors — Abacum | Brex | Metronome

28:47 Do bubbles attract grifters?

31:11 Role of government in bubbles

35:59 Bubble duration vs. severity

37:32 2008 — roots go back to 1992

40:27 Are bubbles connected through time?

43:38 Are we in an AI bubble?

45:06 Nvidia vs. Cisco valuation comparison

46:52 Circular finance in AI

49:16 FP&A at PayPal under Thiel and Musk

52:02 PayPal's referral campaign and LTV/CAC

54:40 Book plug

55:09 Credits

#RunTheNumbersPodcast #Fintech #EconomicBubbles #FinanceHistory #CFO