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In this article, the editor gives you a detailed introduction of "what is the blockchain intelligent contract". The content is detailed, the steps are clear, and the details are handled properly. I hope this article "what is the blockchain intelligent contract" can help you solve your doubts. Let's follow the editor's ideas to learn new knowledge.

What is a smart contract?

A normal contract is an agreement between two or more parties that connects them to something in the future. Alice may pay some money to Bob in exchange for a house that uses Bob (that is, rent). Charlie may agree to repair any future damage to the Denise car in exchange for monthly payments (also known as car insurance).

The difference between smart contracts is that conditions are evaluated and executed by computer code so that they do not need to be trusted. So if Alice agrees to pay Bob $500 for delivery three months from now (that is, in the future), some code can determine if the conditions are correct (Alice has paid Bob? Has it been three months? ) and execute (provided from escrow) without providing either party with the ability to opt out.

The key feature of intelligent contract is that it has no trust in execution. In other words, you don't have to rely on third parties to enforce conditions. A smart contract enforcement should be timely and objective, rather than relying on the other party to honor their words or worse, relying on lawyers and the legal system to correct things.

Intelligent contract

The use of the word "smart" means that these contracts have some innate wisdom. Actually, no. The wisdom of the contract is that it does not require the cooperation of the other party to implement the agreement. A "smart" contract would lock non-paying renters out of their apartments, rather than having to kick out non-paying renters. The implementation of the agreed consequences makes the smart contract powerful, rather than the message inside the contract.

A really smart date takes into account all excusable circumstances, looks at the spirit of the contract, and makes a fair decision even in the darkest of circumstances. In other words, a really smart contract is like a very good judgment. On the contrary, in this case, the "smart contract" is not intelligent at all. It is actually based on rules, following the rules to T, without considering any minor considerations or the "spirit" of the law.

In other words, making the contract untrustworthy means that we really can't have any ambiguity, which will lead to the next problem.

Smart contracts are really hard.

Because of the large amount of centralized marketing in Etay Fong, people mistakenly think that smart contracts only exist in Etay Fong. That's not true. Bitcoin has had a very wide range of smart contract languages called Script since 2009. In fact, smart contracts existed before Bitcoin in 1995. The difference between Bitcoin's intelligent contract language and ethernet is that ethernet is Turing complete. In other words, Solidity (ETH's intelligent contract language) allows more complex contracts, but makes them more difficult to analyze.

Complexity has some major consequences. Although complex contracts can allow for more complex situations, complex contracts are also difficult to guarantee. Even in a normal contract, the more complex the contract, the more difficult it is to enforce the law, because complications add more uncertainty and room for explanation. With smart contracts, security means dealing with every possible way the contract can be executed and ensuring that the contract meets the author's intention.

Execution in a Turing complete environment is tricky and difficult to analyze. Protecting Turing's complete intelligence contract is tantamount to proving that the computer program is error-free. We know that this is very difficult because there are errors in almost all existing computer programs.

Considering writing a normal contract requires years of study and very difficult exams to be qualified. Smart contracts require at least this level of capability, but many are currently written by beginners who don't understand their need for security. This can be clearly seen in various contracts that have been proved to be defective.

Bitcoin's solution to this problem is without Turing integrity. This makes contracts easier to analyze because the possible states of the program are easier to enumerate and check.

Ethernet's solution is to put the burden on smart contract writers. Contract writers need to ensure that the contract meets their intentions.

Smart contracts are not real contracts (at least on ETH)

Although it sounds good in theory to leave the responsibility of the guarantee contract to the author, in practice, this has produced some serious centralization consequences.

Yi Tai Fong put forward the idea that "code is law". In other words, the contract of Etay Fong is the ultimate authority, and no one can veto the contract. Our idea is to show smart contract developers that they are independent. If you screw up your smart contract, in a sense, you should get it. This stops when the DAO event occurs.

DAO represents a "decentralized autonomous organization" and has created a fund in Tai Fong as a way to show what the platform can do. Users can deposit their money in DAO and get a return on DAO's investment. The decision itself will be crowdsourced and decentralized. DAO raised $150 million in ETH when ETH was trading around $20. This all sounds good in theory, but there is one problem. The code is not well protected, causing someone to find a way to consume DAO's money.

Many people say this person regards Qian's DAO as a "hacker". In a sense, it is true that the hacker has found a way to withdraw money from the contract in a way that the creator does not want. But in a broad sense, this is not a hacker at all, it's just that some people take advantage of the eccentricities in smart contracts to their advantage. This is not much different from creative certified public accountants who identify tax loopholes to save clients money.

What happens next is that Etay Fong decides that the code is no longer the law and restores all the money that went into DAO. In other words, the contract writers and investors did something stupid, and the etheric Fong developers decided to rescue them.

The consequences of this incident have been recorded in detail. The Etay Square classic was born, retaining the DAO and the principle that "the code is the law". In addition, developers began to avoid using the Turing-completeness property of Ethernet Square because it proved to be difficult to guarantee. ERC20 and ERC721 standards are the most commonly used intelligent contract templates in Ethernet Fang. it is important to point out that both types of contracts can be written without any Turing integrity.

Smart contracts only apply to digitalization

Even without Turing integrity, smart contracts sound good. After all, who likes to have to go to court to get what reasonably belongs to them? Is it easier to use smart contracts than ordinary contracts?

For example, won't smart contracts benefit real estate? Alice can prove that she owns the house. Bob can remit money for the house and exchange it for the house. No ownership, no trust, fast machine execution, no need for judges, bureaucrats or title insurance issues. Sounds great, doesn't it?

There are two questions. First of all, gathering the Chinese side to implement smart contracts is not real trust. You still need to trust the Chinese side to implement it. No trust is a key feature, so centralized execution doesn't really make sense. For smart contracts to be truly untrusted, you need a de facto decentralized platform.

This leads us to a second problem. In a decentralized environment, smart contracts are valid only if there is a clear link between the digital and physical versions. In other words, whenever the ownership of the digital version of the house changes, the physical version must also change ownership. The digital world requires "understanding" the physical world. This is called the "Oracle problem".

When Alice transfers the house to Bob, the smart contract needs to know that she actually transferred the house to Bob. There are several ways to do this, but they all have the same basic problem. There must be someone who trusts some third party to verify events in the physical world.

For example, a house can be represented as an irreplaceable mark on Etay Square. Alice can transfer the house to Bob through atomic exchange to get a certain amount of ETH. That's the problem. Bob needs to believe that the Token actually represents the house. There must be some Oracle to ensure that transferring the house Token to him actually means that the house is his legal house.

Moreover, even if the authorities say that Token actually represents a house, what happens if Token is stolen? Does the house belong to the thief now? What if Token is lost? Is the house no longer for sale? Can house tokens be reissued? If so, by whom?

It is difficult to solve the problem of linking digital assets to physical assets, whether it is fruit, cars or houses, at least in the context of decentralization. Physical assets are regulated by your jurisdiction, which means that in addition to the smart contracts you create, they trust something in a sense. This means that owning in a smart contract does not necessarily mean having and suffering the same trust problems as a normal contract in the real world. Smart contracts that trust third parties eliminate untrusted killer characteristics.

Even digital assets such as e-books, health records or movies encounter the same problem. The "rights" of these digital assets are ultimately decided by other authorities, and Oracle needs to be trusted.

From this point of view, the oracle is a stupid judge. What you actually get is not just machine execution and simplified execution, but the complexity of coding all possible outcomes using subjectivity and human risk judgment. In other words, by making the contract "smart", you still have to trust someone while writing, which makes writing more complicated.

The only thing that works without Oracle is the digital bearer tool. In essence, both sides of the transaction need not only digital, but also bearer tools. In other words, the ownership of Token cannot be dependent on anything other than the intelligent contract platform. Smart contracts are truly untrustworthy only when they have digital bearer tools.

After reading this, the article "what is the blockchain Intelligent contract" has been introduced. If you want to master the knowledge points of this article, you still need to practice and use it yourself to understand it. If you want to know more about related articles, welcome to follow the industry information channel.

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