Day 6 — Ethereum and the idea of programmable money
In 2013, a nineteen-year-old programmer named Vitalik Buterin wrote a whitepaper proposing a different kind of blockchain. He had been working on Bitcoin Magazine, learning the protocol in detail, and he kept noticing the same limitation. Bitcoin could do one thing very well. It could move bitcoin from one address to another. If you wanted to build any other kind of application on top, you had to either bolt it on awkwardly or build a whole new chain.
Vitalik's proposal was a chain that could run arbitrary programs. Not just "send X to Y," but "if A happens, then send X to Y, but only if B is also true and C has paid into the contract first." Conditional logic. Loops. Math. State. The full power of a general-purpose computer, but distributed across thousands of independent machines, with the same trust properties as Bitcoin's ledger.
He called the chain Ethereum. The programs would be called smart contracts. The runtime that executes them would be called the Ethereum Virtual Machine, or EVM. The native currency that pays for compute on the network would be called Ether (or ETH).
This was the most important conceptual unlock in the history of crypto so far. Almost everything that has happened in the industry since 2015, when Ethereum launched, traces back to this one idea.
Here is the shift in one sentence: Bitcoin proved that you could have a ledger nobody controlled. Ethereum proved that you could have a computer nobody controlled.
Why does that matter? Because a ledger of money is useful but narrow. A computer is general purpose. Once you can run arbitrary programs on a trustless, public, immutable computer, you can build:
- A bank that runs entirely as code and lets anyone in the world deposit, borrow, and lend without permission (DeFi).
- A market for digital ownership of art, identity, membership, music, in-game assets, and increasingly real-world assets (NFTs, broadly).
- A new kind of corporation governed by token holders rather than shareholders (DAOs).
- A stablecoin that holds its peg through a smart contract rather than through a custodian holding dollars in a bank (algorithmic and crypto-collateralized stablecoins).
- Programmable, on-chain reporting for any kind of capital flow (tokenized real-world assets, the thing IMPCT will eventually be building on).
None of these would exist on Bitcoin in their current form. They exist because Ethereum opened the design space.
A few things worth understanding about how Ethereum actually works.
A smart contract is just a program deployed to the blockchain. Once it's deployed, it sits at an address (like a wallet address, but for code). Anyone can interact with it by sending it a transaction that calls one of its functions. The contract's code is public. Its state (what variables it holds, what balances it tracks) is public. Its behavior is deterministic. If you call function transfer(0.5, alice), you can read the code and know exactly what will happen. There is no employee deciding whether to honor the request. The code is the contract.
This is more powerful than it sounds. In traditional finance, a contract is a piece of paper that describes what should happen. When a dispute arises, you go to court. The court decides what the paper meant. The whole system depends on the existence and competence of an enforcement mechanism (the legal system). In smart-contract land, the contract is its own enforcement. If the code says you get paid when the price of ETH goes above $5,000, you get paid when the price of ETH goes above $5,000. There is no negotiation, no discretionary call, no waiting for someone to honor the agreement.
This is also more limited than it sounds. Smart contracts can only act on information that is on-chain. If the contract needs to know the current price of ETH, the temperature in New York, the outcome of an election, or the score of a soccer match, that information has to be brought on-chain by an oracle (we cover oracles in Day 20). And smart contracts are only as correct as their code. If there is a bug, the contract will execute the bug, and there is no customer service to call. The code is the contract, for better and worse.
Ethereum is the original, dominant smart-contract platform, but it is no longer the only one. Solana, Aptos, Sui, Avalanche, and dozens of others are running their own variations of the same idea. There are also chains called Layer 2s that sit on top of Ethereum and execute transactions cheaper and faster while inheriting Ethereum's security (we get into L2s on Day 8). The competitive landscape is real, and it shifts. But the idea of programmable money is now universal. Even Bitcoin is adding limited smart-contract functionality through upgrades like Taproot and second-layer protocols like the Lightning Network.
If you understand Days 1 through 5 and you understand today, you understand more about how blockchain technology actually works than 95% of people who have an opinion about it. Tomorrow we tie it together with a recap and an applied test, and then Week 2 opens the door to the broader ecosystem: stablecoins, exchanges, custody at scale, mining versus staking, and the difference between Bitcoin's world and everything that has been built on Ethereum-style infrastructure.
You showed up six days in a row. That's not nothing. That's the rate at which most things worth doing get done.
See you tomorrow.
Glossary
| Term | Definition |
|---|---|
| Ethereum | The second major blockchain, launched in 2015. The original general-purpose smart-contract platform. |
| Smart contract | A program deployed to a blockchain that executes deterministically when called. The code is the contract; there is no human in the loop. |
| EVM (Ethereum Virtual Machine) | The runtime environment that executes Ethereum smart contracts. Other chains compatible with the EVM (Polygon, Arbitrum, Base, etc.) are called "EVM-compatible." |
| Ether / ETH | The native currency of the Ethereum network. Used to pay gas fees and as a store of value. |
| Vitalik Buterin | The co-founder of Ethereum, who proposed the protocol in 2013 at age 19. Still one of the most influential figures in crypto. |
| DeFi (Decentralized Finance) | Financial applications (lending, trading, derivatives, asset management) built as smart contracts rather than as company-run services. Covered in Week 3. |
| DAO (Decentralized Autonomous Organization) | An organization governed by smart contracts and token-holder voting rather than by a traditional corporate structure. |
| Layer 2 | A blockchain that sits on top of another (typically Ethereum) and inherits its security while offering cheaper or faster execution. Covered in Day 8. |
| Oracle | A service that brings off-chain information (prices, weather, election results) onto the blockchain so smart contracts can use it. Covered in Day 20. |
Reality check
Bitcoin is a ledger nobody controls. Ethereum is a computer nobody controls. In your own words, why does the second one open up so much more than the first?
If you can describe how going from "a single rule (move BTC)" to "any rule you can program" multiplies the design space (lending, exchanges, ownership systems, governance, programmable capital), you have the lesson. If you cannot, re-read the core. This is the conceptual hinge for the rest of the course.
Read deeper
1. A brief history of Ethereum by The Block
The full origin story, from the 2013 whitepaper to the present.
Read on IMPCT (curated commentary) | Read original (theblock.co)
Deven's take. Worth reading for the texture of the early years. Pay particular attention to two moments: the 2016 DAO hack (which forced Ethereum to make an existential decision about whether code is law) and the 2022 transition from proof-of-work to proof-of-stake (called "The Merge," one of the most technically impressive upgrades in software history). Both events shaped what Ethereum is today.
2. Who is Vitalik Buterin? by The Block
The story of the most influential thinker in crypto.
Read on IMPCT (curated commentary) | Read original (theblock.co)
Deven's take. Vitalik is unusual. He is a working researcher who never stopped being one. He still publishes blog posts on cryptography, economics, and governance with the same depth he had at nineteen. Reading him is one of the highest-leverage things you can do in this space. He doesn't pretend to know things he doesn't, and he is comfortable updating his views in public. His blog at vitalik.eth.limo is the single most under-recommended resource in crypto. Bookmark it.
3. What is Ethereum's roadmap? by The Block
Where Ethereum is heading next.
Read on IMPCT (curated commentary) | Read original (theblock.co)
Deven's take. Ethereum's roadmap is one of the few in tech that is genuinely public, technical, and reviewable. The Block does a good job of distilling it into chunks. The five phases (The Merge, The Surge, The Verge, The Purge, The Splurge) sound like fantasy novels but each describes a real technical milestone that affects everything built on the chain. Knowing the roadmap means you can read a news article about "Ethereum's next upgrade" and immediately understand which phase they're talking about and what it changes.
4. The blockchain trilemma by The Block
The structural tradeoff every blockchain has to make.
Read on IMPCT (curated commentary) | Read original (theblock.co)
Deven's take. This is the framework that explains why every blockchain feels different. The trilemma: a chain wants to be secure, decentralized, and scalable, but it can only optimize two of the three at the base layer. Bitcoin chose security and decentralization. Solana chose security and scalability. Ethereum is trying to keep all three through Layer 2s (we'll cover this in Week 2). Once you have the trilemma in your head, you can evaluate any new chain by asking which two it picked. Most explanations of "why this chain is special" reduce to the trilemma when you push on them.
5. Vitalik Buterin's blog (ongoing)
The primary source.
Read on IMPCT (curated reading list of his most important posts) | Read original (vitalik.eth.limo)
Deven's take. I cannot recommend this resource highly enough. Some of his posts are intentionally technical and will not be useful for most readers. Others, especially the governance and policy essays, are accessible and genuinely rewire how you think about coordination problems at scale. Three I'd point you to as starting reads: Endgame (his vision of where Ethereum is heading), Soulbound (the case for non-transferable tokens, the seed of identity-on-chain), and Why proof of stake (the strongest defense of Ethereum's consensus mechanism). I'll curate a top-ten list on the IMPCT page over time.
Tomorrow
Week 1 recap. Tomorrow is the most important day of the course so far, not because you'll learn new material, but because you'll find out what stuck and what didn't. You'll apply everything from Days 1 through 6 to a real crypto news headline and decode it sentence by sentence. The point isn't to test you. The point is to surface the parts of your understanding that are sharp and the parts that are still fuzzy. Both are useful. Bring the same attention you've brought all week.
See you in the morning.
Preview reader
You are reading a private preview of IMPCT Institute. If something landed, didn't land, or felt confusing on this lesson, tell us. Short notes are useful. Long notes are useful. No notes are also fine.