## Programmable Cryptography in the context of Plurality

@oskarth, Ethereum Cypherpunk Congress / Devcon
Bangkok, 2024

---

## Intro

- Now: Independent researcher
- Programmable cryptography
- Writing a book on ZK, zkintro.com
- Previously:
- Created mopro, tool for client-side proving
- Created Waku, p2p messaging protocol

Note:
Slide 1

---

## Takeaway

**Programmable Cryptography will enable
a more ⿻ plural world.**

Note:
Slide 2
Need to understand what we mean by programmable cryptography, and plurality

---

## Agenda
- What is Plurality?
- What is Programmable Cryptography?
- What are some problems that Plurality deals with?
- How can Progammable Cryptography help with these?
- Where do we go from here?

Note:
Slide 3

---

## plurality.net


Note:
Slide 4
Plurality, book written by Glen Wyle, Audrey Tang, and Community
Vision of digital democracy in the 21th century

---

## ⿻ Plurality

- ⿻: Plurality/數位, both digital and plural
- Digital democracy in the 21th century
- Neither mountain-man nor king-tyrant
- Tech for collaborating across social differences

Note:
Slide 5
As nouns or verb
Mountain-main Libertarianism, focused only on individual in isolation
King-tyrant Technocracy, Big Tech top down control
Taiwan as a case study
Back to the roots of original Internet vision

---

## Programmable Cryptography

- Cryptography: Securing digital information
- Prog crypto: Cryptography + Computation
- Tools: ZK, MPC, FHE
- Ex: Prove you 18+ with passport using ZK
- Not revealing anything else
- General-purpose privacy and succinctness
- If ZK is single-player, MPC/FHE multi-player

Note:
Slide 6
Cryptography with tools like signatures and encryption
Rely on it for current Internet to do everything
Zero Knowledge Proofs, Multi-Party Computation, Fully Homomorphic Encryption
We'll look at this more in specific examples

---

### Cryptographic Matter

- Exists everywhere
- Websites (HTTPs), Digital IDs (RSA), Emails (DKIM)
- Bank statements, government documents, ...
- Leverage existing signed data to enable plurality

Note:
Not starting from scratch
Raw material we can shape

---

## Digital Democracy

- Enshrined ⿻ Freedom and rights as foundation for a digital democracy
- similar to OS and apps, kernel/user space
- Dimensions identified, builds on each other
1) Identity/Personhood, 2) Association, 3) Commerce/Trust, 4) Contracts/Property, 5) Access
- Need a robust but flexible foundation

Note:
OS, access control etc, robust foundation
Build on each other; on top we can build apps
Hardness - trustworthy, crypto, sound money
Look at each dimension in turn
Disclaimer: simplified view, mapping to progcrypto, not complete

---

## 1) Identity/Personhood


- Core Challenge: Anonymity vs Centralized Control
- Without secure identity, digital democracy fails

Note:
"On Internet no one knows you are a dog"
Don't want either extreme
Without secure identity, digital democracy fails

---

## 1) Identity/Personhood (cont)

- ZK Identity as a building block
- Selective disclosure (Anon-Aadhaar and OpenPassport)
- Key idea: take signed data and make proofs
- **New**: Georgia and Buenos Aires ZK ID
- Identity as intersection: Social relationships
- Verification through multiple contexts
- Social key recovery (3/5 friends/factors)
- Ex: Cursive PSI - shared experience
- Polycentrism

Note:
Aadhaar used by 800m, signed PDF doc, loans, jobs etc
AA proof w/o revealing address; also offline proof still ok; live!
Gitcoin Passport combining multiple for sybil-resistance
Not SPOF biometric; intersection

---

## 2) Association


Beyond public vs private; we live in *common context*

Note:
Too simplified only private or public
Free association requirement for free society
But it involves establishing and protecting context
Threat is e.g. unilateral oversharing

---

## 2 Association (cont)

- How do we create secure common contexts?
- Cryptography useful for protecting context
- Internal threat: disclosure, unilateral oversharing
- Ex: MACI private, collusion-resistant voting
- Creating a private, parallel universe
- Ex: Private Set Intersection with FHE

Note:
Privacy for groups, but often threat internal;
Norms and punishment after fact but
E.g. colluding/bribery buying votes
Impossibility of disclosure: can't be credibly shared outside
More examples: Gridlock multilateral netting

---

## 3) Commerce/Trust

- Cash vs CBDC vs Crypto
- Cash: Dumb but works
- Digital world enables more (good and bad)
- Beyond tokens: social relationships and trust

Note:
Native money for Internet, but how?
Private, fungible, not control/surveillance
Credit networks, community currencies
OSS contributions
Group freedom interest

---

## 3) Commerce/Trust (cont)

- Private, fungible money?
- Monero/Zcash, Tornado Cash
- Community-based trust network
- E.g. NK privacy pools, "proof of innocence"

Note:
Want fungible money
Community-trust networks
OP disagrees a bit with "too" conextual money, want credible neutral
Maybe no full anon, like NK hacks
All using ZK tech, privacy pools prove exclusion from known hacks
Other ideas: Banks on top of Ethereum, MPC transparency etc

---

## 4) Contracts/Property

- Digital assets: storage, compute, data
- underutilized, need better sharing protocols
- What should A learn about B's data?
- Take signed data and prove properties
- Ex: ZK-ML private input or model
- Also...

Note:
Critical for digital age
Also physical, land, compute; cloud providers powerful
Opportunity for progcrypto

---

## 4) Contracts/Property (cont)

- Ex: TLSNotary
- Free your data (prove bank balance)
- W/o revealing everything
- Ex: IPFS/Filecoin, et al
- Storage marketplace, incentives
- Enable sharing, cooperation
- Maintain control, privacy

Note:
Enable sharing, cooperation
Maintain control, privacy
Marketplace
Decentralized alternatives

---

## 5) Access

- Access as fundamental right
- Availability but also integrity
- Information integrity
- Deep fakes and fake news?
- New standard: signature of photo/content
- More signed data:
- ZK signed data and prove valid operations
- Prove emails with zk-email
- Openness and trust

Note:
Access as fundamental right
Not just availability, need integrity
Ability to verify and maintain privacy
Openness and trust
E.g. Reuters standard ops, grey/resize/crop
Time and place, ~trust Canon/Camera

---

## Depth vs breadth frontier


Note:
Slide 17
Push outward, production possibility frontier
Bandwidth
Same for prog crypto! More rich things
Concise proofs, what is private/public clear
Also more participants with MPC and FHE
Seen more flexibility

---

### Programmable Cryptography

Hard and flexible, like bamboo and carbon fiber


Note:
Slide 18
We want to be both robust and flexible
Cryptographic hardness, sound money
But also flexible to the world we live in
Anchored in old, like bamboo
But also new into the digital future, carbon fiber
Programmble Cryptography allows us to build
new institutes and systems that leads to a more free and democratic world in 21th century

---

## Plurality

*develop tools that allow greater cooperation and consensus at the same time as they make space for greater diversity*

(Plurality book, Chapter 5-0)

Note:
Slide 18
Big part of plurality in action is this

---

## Summary

**Programmable Cryptography will enable
a more ⿻ plural world.**

- We are moving into a digital and plural world
- Programmable cryptography is a useful tool
- We need more conversations between technologists, researchers, policy makers etc

Note:
Slide 19

---

## Thanks!

- Questions?
- oskarth.com / @oskarth

Note:
Slide 20

---