The ultimate question of asset allocation: if 'up 20 years' and 'down 80%' are each 50-50, which allocation lives well in both?

In 30 seconds: James says this is the ultimate question every investor must answer for themselves — assume two things each have a 50% chance: ① the market rises for 20–30 years straight from today, with the bear market not arriving for 20 years; ② today is the top, and over the next three years it falls 80%. Don’t prepare for only one (most people prepare only for “up forever,” never imagining three years of decline plus job loss). Your task is to find one allocation that, whichever happens, lets you eat well, sleep well, worry-free, earn, and live well — without being forced to change your life by market swings. Investing isn’t about making the most; it’s about being able to hold with peace of mind and stay alive in any scenario.¹

Two scenarios, each 50%

At the top of 00575, James collapses asset allocation into one “you must answer this yourself” slide (deck slide 21):¹

1. Big bull scenario: if from today the market just keeps rising, for 20–30 years, with the bear not coming for 20 years — does your allocation earn? Does it earn the biggest position you’d want to earn?
2. Big bear scenario: if today is the top and over the next three years it falls 80% (and you may lose your job at the same time) — can your allocation still let you stay alive, at ease, eating and sleeping well?

The key is: both must be handled “simultaneously” for your allocation to be correct. “Everyone prepares for the market rising forever, and never thinks: if the market falls for three years and I also lose my job, is my allocation still alive?” And James’s assumption is — the probability of each scenario is 50%; you can’t bet only the first will happen.¹

The test: not “make the most,” but “live well in both”

• Chasing only the best returns = praying: “If you only seek the best returns, you’re hoping and praying the future only rises and never falls; if the market falls, you can’t survive.” So maximizing returns is not the goal.¹
• The real goal: “not to make the most, but to be able to hold with peace of mind, stay alive forever, eat well, sleep well, have money to spend, spend when you want. Market ups and downs, losses and gains, everything about the market — has nothing to do with me.”¹
• No standard answer; answer it yourself: everyone’s age, cash flow, debt, and risk tolerance differ, so “there’s no standard answer, you have to answer this question yourself” (echoing 投資沒有標準答案).

Two extremes that easily fail

James specifically flags two “one-sided” wrong allocations:¹

• Preparing only for the rise (all in, plus leverage): whether you use unsecured credit, pledge loans, or a mortgage — the moment the big-bear half happens, you’re out. So borrowed money must also pass the “if it falls 80% am I still alive?” test (the borrowing-fitness rule is in 我適不適合借錢投資利率多高值得借).
• Preparing only for the fall (all cash): “If you hold cash, the fall has nothing to do with you, but the rise also earns you nothing — so that allocation is also wrong.” You dodged the bear but lost the 50%-probability bull (why cash is air, see 現金是空氣).

The correct allocation is a barbell-style balance: keep enough of a safe position / cash flow to survive the three-year 80% drop (extended into 三層防線 and 十五年現金流), while holding enough Nasdaq growth to catch the 20-year bull; trim peaks when it rises and refill when it falls with 聰明再平衡法. That way, whichever half happens, you don’t have to change your life.

This is the “why” behind all of CLEC’s allocation pages

• 現金是空氣‘s “four-tier withdrawal-rate allocation” is the static solution to this question (multiples/withdrawal rate decide the offense/defense ratio).
• 三層防線 specifically answers “the big-bear half happening in your retirement year.”
• 聰明再平衡法 is the mechanism that auto-adjusts you between the two scenarios.
• This page is their shared starting point: only by accepting “two extremes, each 50%” do you understand why you must hold both growth and defense, rather than betting everything on a single scenario.

⚠️ “Down 80% / up 20 years, each 50%” is a thought experiment James uses to force out “both sides must be able to survive” — not a market prediction or probability estimate. Actual allocation ratios vary by person; this page organizes his allocation mindset, not personalized investment advice.

Footnotes

1. CLEC James, 長篇 00575 “What truly teaches you is not the result, but the process!”, 2026-07-25, ultimate question of asset allocation @27:30–32:30. Same point on deck slide 21 raw/docs/簡報資料/00575… (“If the bear market won’t come for 20 years… if today is the top and the market falls 80% or more over the next three years… each with a 50% chance, what is the best allocation strategy — this is the ultimate question investing must answer”). Transcript in raw/transcripts/長篇/00575…. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶