In the fast-moving Web3 industry, reading technical books published several years ago—now considered "classics"—in 2026 holds significant value.

Why? Because the "Why" (the fundamental philosophy) behind the technology remains far more vivid in early literature than in the latest documentation.

In this article, based on three classic books, I will revisit the foundational theories of blockchain, check the "Future Predictions" made back then against the "Current Solutions (2026 Implementations)," and explore where blockchain is heading now that AI and Quantum Computing have entered the practical stage.

📚 The "Bibles" Referenced

1. "Blockchain: Theory and Practice" (Similar scope to Mastering Bitcoin)
2. "The Textbook for Understanding Blockchain Structure and Development"
3. "Blockchain Revolution" by Don Tapscott and Alex Tapscott

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Chapter 1: The Structure of "Trust" Redefined by Blockchain

Before diving into technical explanations, let’s clarify the definition of "Trust" at the root of the architecture.

1.1 Mathematical Assurance of Social Capital

As stated in Blockchain Revolution, an ideal society is one rich in "Social Capital," where "courage worthy of praise is rewarded."

Traditionally, this "courage" (honest behavior) was guaranteed by Centralized Intermediaries (TTP: Trusted Third Parties) like banks and governments. However, these can become "Single Points of Failure (SPOF)" and incur mediation costs.

Blockchain replaced this trust with "Cryptographic Proof" and "Game Theoretic Incentives."

• Cost of lying > Profit gained from lying

As long as this inequality holds, the system autonomously continues to record the "truth." This is the true meaning of "Trustless." It doesn’t mean "trust no one"; it means "you trust the protocol so you don’t have to trust anyone else."

1.2 Web3 and the "Internet of Value"

The concept proposed in early literature has become clearer today:

• Web2 (Internet of Information): Copying is easy. Democratization of information.
• Web3 (Internet of Value): Copying is impossible (prevention of double-spending). Democratization of value.

"Value" here isn’t limited to currency. It includes identity, copyright, voting rights, and the "autonomous economic activities of AI" discussed later.

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Chapter 2: Technical Details Supporting Bitcoin’s Robustness

Let’s look back at the mechanisms of Bitcoin with high resolution.

2.1 The Beauty of State Management: The UTXO Model

In Bitcoin, there is no variable called "Balance" in the database like in a bank account. There is only a collection of UTXOs (Unspent Transaction Outputs).

• Input: References a past transaction (where the money came from).
• Output: Specifies the new owner (who the rights are transferred to).
• Script: A simple program (stack-based language) that verifies the validity of the transaction.

graph LR
A[Tx A: 10 BTC] -->|Input| B(Tx B)
B -->|Output 1| C[To Alice: 3 BTC]
B -->|Output 2| D[To Bob: 7 BTC]
style A fill:#f9f,stroke:#333,stroke-width:2px
style B fill:#bbf,stroke:#333,stroke-width:2px
style C fill:#bfb,stroke:#333,stroke-width:2px
style D fill:#bfb,stroke:#333,stroke-width:2px

This model has the advantages of "ease of parallel processing" and "high privacy (easy to use disposable addresses)." On the other hand, it is unsuitable for complex state management (stateful processing) like Ethereum.

2.2 The Key to Tamper Detection: Merkle Trees

The block header contains the "Merkle Root," which is a summary value of all transactions included in that block.

• Mechanism: A binary tree structure where transaction hashes are paired and hashed repeatedly until finally one hash value (the root) remains.
• Benefit (SPV Nodes): Lightweight nodes (SPV) like smartphones can verify "whether a specific transaction is included in a block" using only the Merkle Path ($O(\log n)$ complexity) without downloading all data.

2.3 Consensus: The Essence of Proof of Work (PoW)

PoW is not just a calculation competition. It is a converter that transforms "physical world resources (electricity/hardware)" into "digital world security."

• Nonce: Searching for a 32-bit integer such that the hash value is less than or equal to the Difficulty Target.
• Probabilistic Finality: If you wait for "6 confirmations" (about 1 hour), the probability of the transaction being overturned becomes astronomically low.

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Chapter 3: The 2026 "Answer Key" — Scalability and Ethereum

When these books were published (around 2017-2020), the biggest challenge was Scalability. What happened to the "prophecies" of that time?

3.1 The Defeat of Plasma and the Victory of Rollups

"Plasma," a scaling technology that was once considered promising in early technical texts, is almost unused in 2026.

• Plasma’s Failure: The Data Availability Problem. Because it only wrote the hash of the data to the parent chain, if the Operator maliciously hid the data, users risked being unable to withdraw funds.
• Rollup’s Victory: They adopted a method of writing "transaction data (compressed)" to L1 (Ethereum) as well as processing results. This allowed them to fully inherit L1 security.

Today, Optimistic Rollups (using fraud proofs) and zk-Rollups (using zero-knowledge proofs) are the center of the ecosystem.

3.2 Account Model and Smart Contracts

Ethereum adopted the Account Model instead of UTXO. This allowed it to hold "State" on the EVM (Ethereum Virtual Machine), enabling complex applications (DApps).

• EOA (Externally Owned Account): Users holding private keys.
• CA (Contract Account): The code itself.

The trend in 2026 is "Account Abstraction (ERC-4337)," which makes EOAs programmable like CAs. This is solving the biggest UX challenge of Web3: "Loss of Private Key = Loss of Assets."

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Chapter 4: AI × Blockchain — The Arrival of the Agentic Economy

From here, based on the knowledge from the books, I will explain the most important topic of 2026: Fusion with AI.

4.1 "Bank Accounts" for AI Agents

The books talked about "IoT × Blockchain," but the true form was "AI Agent × Blockchain." While it is a high hurdle for humans to operate Web3 wallets, for AI, Smart Contracts are the easiest APIs to handle.

• Micropayments: AI pays usage fees for inference APIs in real-time, in units of $0.0001.
• Autonomous Asset Management: AI agents manage and operate their own funds using DeFi protocols.

4.2 Proof of Humanity / Content Authenticity

With Generative AI flooding the world, technology to prove "whether this was made by a human or an AI" is essential. Blockchain (public ledger) plays a vital role here as well. By carving the hash of the creation process into the chain, the Origin of digital content becomes immutable.

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Chapter 5: Cryptography in the Quantum Era

Finally, I will touch on "Quantum Resistance," a topic I am particularly watching. While classical texts state that ECDSA (Elliptic Curve Digital Signature Algorithm) is secure, if a quantum computer capable of implementing Shor’s algorithm appears, the security of current blockchains will collapse.

5.1 Specific Threats

• Deriving Private Key from Public Key: ECDSA and RSA rely on the difficulty of prime factorization or discrete logarithm problems, but quantum computing can solve these in polynomial time.
• Hash Function Collisions: Grover’s algorithm reduces the computational complexity of hash searching to $O(\sqrt{N})$ (although this is said to be manageable by doubling the key length).

5.2 The 2026 Countermeasure: Migration to PQC

Currently, major chains like Ethereum are preparing to migrate to Post-Quantum Cryptography (PQC).

• Lattice-based cryptography: A leading candidate for quantum resistance.
• STARKs: A Zero-Knowledge Proof technology considered quantum-resistant because it relies only on hash functions.

Precisely because blockchain promises to "preserve past records forever," cryptographic design anticipating computational power 10 or 20 years from now is required today.

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Conclusion: Know the Theory, Implement the Future

The mathematical beauty told in Blockchain Theory. The gritty implementation details learned in Textbooks. The enthusiasm for social change depicted in Revolution.

These three perspectives have not faded even in 2026. Rather, with the addition of new variables like AI and Quantum Technology, their importance has increased.

What engineers need now is the ability to oscillate between the "Micro Perspective" (understanding EVM opcodes) and the "Macro Perspective" (AI economy and Quantum resistance).

The idea of "P2P Electronic Cash" presented by Satoshi Nakamoto in the white paper is now evolving into a "Foundation for an Economic Zone where Autonomous AI flies about." If you are going to participate in this grand experiment, now might be the most exciting time.