The major function of a public blockchain, compared to private blockchains, is its ability to preserve truth through the immutability that defines it. As a distributed ledger, the blockchain records various forms of data that reflect the true state of things, whether in the physical or digital world. From this, we can infer that the information recorded by the blockchain is accurate, verifiable, and trustworthy. In other words, the blockchain records truth. The public blockchain’s greatest advantage, however, is not only its ability to record truth but also to preserve it over time. This article focuses on the second function of public blockchain: preserving truth. First, we will examine why truth preservation matters and why it is a crucial problem. Then, we will compare how private and public blockchains record and preserve truth, highlighting why public blockchains perform better. Finally, we will explore the limitations of public blockchains despite their strong potential to safeguard truth.

The Human Drive to Preserve Truth.

Humans record information for many reasons, among them is remembering, verifying, and preserving the truth about what happened. In trade, agreements, ownership, and everyday transactions, record-keeping exists primarily to safeguard the truth about what truly occurred between parties. Why is preserving truth so essential?

Imagine someone buys a used phone without receiving a receipt. Later, the phone is discovered to be stolen. The police trace it, and since the buyer has no record to prove the purchase, they are accused of theft. The real owner, however, presents a receipt and reclaims the phone. In this example, the absence of a verifiable record meant no source of truth could confirm the buyer’s innocence. Human interactions, from ownership and agreements to transactions, often depend on trusted records. Yet, these records can be altered, forged, or deleted. That’s where blockchain, especially public blockchains, come in: to make truth verifiable, tamper-proof, and permanent.

Why Centralized Records Fail to Preserve Truth.

Consider another example. A customer buys a phone from a store and gets a receipt. The store attendant, however, sells the phone at an inflated price, then edits the record in the company’s system to conceal it. This scenario demonstrates how truth can be manipulated when a centralized authority controls the ledger. Or think of a land deal where a seller transfers the same land to two buyers. The second buyer, lacking access to a verified public record, cannot confirm whether the land has already been sold. These examples illustrate how centralized systems fail to guarantee truth when records can be changed, hidden, or corrupted.

Public blockchains solve this by ensuring that no single party can unilaterally alter the history of the blockchain. Once a transaction or record is verified and added to the chain, it becomes nearly impossible to modify without public consensus.

Comparing Private and Public Blockchains in Preserving Truth.

When discussing truth preservation, two key questions arise:

1. What type of ledger records the truth, and is it immutable?
2. Who controls the validation and recording of that truth?

Blockchain, in general, is a digital distributed ledger that records information, transactions, and states of reality. Each block contains a set of records that link to the previous one, forming an immutable chain. If any past block is altered, all subsequent blocks become invalid, ensuring data integrity and truth continuity.

Private blockchains, however, are governed by a closed group of entities or individuals. These participants decide what goes into the ledger and can edit or delete entries. Control over validation and access determines how much the system can be trusted and how reliably it preserves truth. In contrast, public blockchains are open, decentralized, and resistant to manipulation. No single entity controls the data. Every participant can verify what is true, and any attempt to alter information would require consensus from the majority of the network. This decentralization ensures that truth is collectively maintained rather than privately managed, which represents a crucial distinction between public and private blockchains.

Decentralization: The Heart of Truth Preservation.

Public blockchains safeguard truth primarily through decentralization and immutability. Unlike centralized systems, where a few individuals can alter data at will, public blockchains distribute power across a network of participants. Once information is added to a public blockchain and another block is built on top of it, changing the earlier record becomes practically impossible. This immutability is reinforced by consensus mechanisms and processes that ensure the network agrees on the true state of the ledger before any update occurs.

The transparency of public blockchains also enhances verifiability. Every participant can see the recorded data, validate transactions, and detect unauthorized changes. Even if a piece of information is modified, the system maintains visibility into what was changed and when, allowing the truth to be reconstructed. This transparency ensures that truth is not only preserved but also traceable, making blockchain a historical record that cannot easily be rewritten.

The Reversibility Challenge of Public Blockchains.

However, preserving truth on public blockchains comes with a unique problem of irreversibility. Because immutability prevents alteration, correcting a mistake becomes extremely difficult. If every block could be easily edited, the blockchain would no longer be trusted as a source of truth. But this also means that genuine errors are recorded permanently. For example, in the earlier scenario of a store attendant entering the wrong price for a phone, correcting that mistake on a public blockchain would be difficult. The ideal solution would not be to delete or overwrite mistakes but to record corrections transparently, just as banks record reversals rather than deleting transactions. This approach ensures both truth and accountability coexist. Hence, while immutability strengthens trust, it also creates a design challenge in how to correct errors without compromising integrity.

Why Preserving Truth Matters.

The preservation of truth is central to ownership, accountability, and history. From financial records to property rights, truth defines legitimacy. A verifiable, immutable record of truth protects individuals and institutions from manipulation and fraud. Public blockchains achieve this through decentralization, open governance, and transparency, qualities that make them a reliable mechanism for preserving the true state of things. Yet, questions remain:

• Can private blockchains still preserve truth if their custodians are trustworthy?
• Should public blockchains evolve to allow reversible actions while maintaining transparency?
• How can we balance immutability with correction when human error is inevitable?

These questions highlight the ongoing evolution of blockchain technology. As we continue to improve public blockchain systems, the mission remains the same: to preserve truth in a way that no single entity can rewrite history. By reimagining blockchain as a truth-preserving infrastructure rather than just a transaction system, we unlock its deepest social and technological potential by ensuring that truth itself stays on-chain, verifiable, and untampered for generations to come.