Key Principle
The PPPP framework maps potential futures as concentric cones fanning outward from the present into nested zones. Adapted from Stuart Candy (2009), it provides the book's foundational visual model. The components:
- Probable (narrowest) -- What is likely to happen. Where most design operates. All design methods, education, and evaluation are oriented here.
- Plausible -- What could happen given current knowledge. The space of scenario planning.
- Possible (widest) -- Scientifically possible futures with a believable path from today. This is where speculative design operates.
- Fantasy (beyond possible) -- Few links to reality. The authors have "little interest" here.
- Preferable -- A distinct wedge cutting across Probable and Plausible, defined by values and debate, not prediction.
The framework's key insight: the Preferable is not a subset of the Probable. Design's job is to populate the Preferable zone with tangible proposals that enable democratic negotiation of what should happen. (Chapter 1)
Why This Matters
Without these distinctions, futures discourse collapses into either prediction (probable only) or fantasy (possible only), leaving no actionable space for democratic negotiation. Most design infrastructure -- methods, education, professional evaluation, market incentives -- pulls work toward the Probable cone. This means design defaults to reinforcing the status quo, optimizing within existing systems rather than questioning whether those systems should exist.
The framework also reveals a political gap: "Preferable for whom?" is currently determined by government and industry, with citizens participating only as consumers and voters. Speculative design aims to populate the Preferable zone with tangible proposals that enable broader public participation in deciding which futures are worth pursuing. The question of who defines the preferable is the framework's most politically charged and deliberately unresolved tension.
Speculation has a dual function: it both increases the probability of desirable futures and enables early detection of undesirable ones. This asymmetry justifies speculative work even when specific proposals are never realized. (Chapter 1)
Good Examples
Scenario Planning (Plausible zone): Originated with Royal Dutch Shell in the 1970s. Not prediction but systematic exploration of alternative futures for organizational preparedness. Demonstrates how even corporate practice benefits from moving beyond the Probable. (Chapter 1)
Michio Kaku's expansion of the Possible: In Physics of the Impossible, Kaku identifies only two things truly impossible according to current science: perpetual motion and precognition. All other changes -- political, social, economic, cultural -- are merely difficult to imagine paths toward. This radically expands the legitimate space for speculation. (Chapter 1)
Expert role inversion: In speculative scenarios, the expert's role is "not to prevent the impossible but to make it acceptable" (David Kirby, Lab Coats in Hollywood, cited Chapter 1). Experts lend plausibility to speculation rather than constraining imagination -- they help proposals earn residence in the Possible cone rather than being dismissed as Fantasy.
Counterpoints
Fantasy vs. Possible boundary: Speculative design requires two conditions for the Possible zone: (1) scientifically possible, (2) a believable series of events connecting present to scenario, even if fictional. Work that abandons these constraints loses its critical power and slides into Fantasy. (Chapter 1)
Preferable as political contest: The framework deliberately leaves "preferable for whom?" unresolved. This is not a flaw but a feature -- it prevents the designer from becoming a prescriptive authority. However, it means the framework alone cannot guide action; it must be paired with genuine democratic engagement. (Chapter 1)
Probable-zone gravitational pull: Operating in the Possible zone requires new design roles, contexts, and methods that do not yet have established institutional support. The entire apparatus of professional design -- client relationships, evaluation criteria, career incentives -- rewards Probable-zone work. Speculative practitioners must actively resist this pull. (Chapter 1)
Key Quotes
"It is hard to say what today's dreams are; it seems they have been downgraded to hopes -- hope that we will not allow ourselves to become extinct, hope that we can feed the starving, hope that there will be room for us all on this tiny planet. There are no more visions." -- Dunne & Raby, Chapter 1
"By speculating more, at all levels of society, and exploring alternative scenarios, reality will become more malleable and, although the future cannot be predicted, we can help set in place today factors that will increase the probability of more desirable futures happening." -- Dunne & Raby, Chapter 1
"Market-led capitalism had won and reality instantly shrank, becoming one dimensional." -- Dunne & Raby, Chapter 1
"Now, a younger generation doesn't dream, it hopes; it hopes that we will survive, that there will be water for all, that we will be able to feed everyone, that we will not destroy ourselves." -- Dunne & Raby, Chapter 1
Rules of Thumb
- Use the cone as a diagnostic: if all your work lives in the Probable zone, you are reinforcing the status quo, not speculating.
- The Possible zone requires two anchors: scientific possibility and a believable narrative path from today. Drop either and the work slides into Fantasy.
- Always ask "preferable for whom?" -- the answer reveals hidden assumptions about power and values.
- Futures are a medium for imaginative thought, not destinations to be predicted or prescribed.
- Speculation has a dual function: increasing probability of desirable futures AND early detection of undesirable ones.
- The preferable is defined by values and debate, not extrapolation from current trends.
Related References
- Core Framework: Speculative Design as Social Dreaming - The broader speculative design thesis this framework supports
- Critical Design as Attitude - The attitude needed to operate in the Possible zone
- Functional Fictions and Biodesign - Applied example of working in the Possible zone with biotechnology