Terms and conditions

It is the contract between you and us. The Spanish version governs in Mexico, because Mexican law requires it for standard-form contracts.

These terms govern the use of paretolearn.com and the Pareto Learn web application. They are a standard-form contract: you do not negotiate them line by line, but you are entitled to have them written legibly and free of disproportionate or unfair obligations.

If you disagree with any part, the exit is not to use the service. If something strikes you as unfair, write to us before leaving: we would rather fix it.

Legal basis: Art. 85 of Mexico's Federal Consumer Protection Law.

By using the service or creating an account you accept these terms and the privacy notice. You state that you have legal capacity to be bound and that the information you give us is truthful.

The service is not aimed at minors and, in particular, it is not directed to children under thirteen. We do not verify anyone's age, so this is a condition of the contract, not a technical control.

We publish our own original explanations of the ideas in books. We do not publish the books, nor licensed summaries, and we are not affiliated with their authors.

Pareto Learn's explanations are our own original work: analysis, context and critical commentary written by us. What we explain are the ideas, methods and concepts contained in works of non-fiction, which article 14, section I of Mexico's Federal Copyright Law expressly excludes from copyright protection. They are not summaries, compendia, adaptations or paraphrases of those books, they do not reproduce their text beyond limited quotation, and they neither replace reading them nor interfere with their normal exploitation. Where we quote verbatim we do so under article 148, sections I and III of that same law: the amount taken can never be considered a simulated and substantial reproduction of the work's content, we invariably cite the source, and we do not alter the work. We are not licensed by their authors or publishers, and for what we do we do not need to be.

We have no affiliation, sponsorship or endorsement relationship with the authors, publishers or rightsholders of the works we analyse. References to titles, authors and brands are descriptive, for identification and commentary.

Nothing we publish is professional advice. It is not medical, legal, financial, tax or psychological advice and should not be taken as such. We work hard to explain other people's ideas well, but we do not warrant that those ideas are correct or that they will work for you.

Legal basis: Art. 32 of Mexico's Federal Consumer Protection Law, which requires all information about a product or service to be truthful, verifiable and not misleading.

• You need a valid email address and you must verify it. The account is personal and non-transferable.
• You are responsible for keeping your password secret and for what happens in your account. Tell us if you think someone else got in.
• You can close your account whenever you like by writing to contact@paretolearn.com. That is the only route today; we are building account-level deletion.
• We may suspend or close an account that breaches these terms, with prior notice unless the breach is serious or ongoing. If the account had a paid subscription and the closure is not due to a serious breach attributable to you, the unused proportional part is refunded.

Without an account, one explanation a month. With a free account, three. With a subscription, no cap. We say it here, not when you hit the wall.

Counters reset on the first day of each calendar month. The limit for people without an account is kept in a first-party cookie in your browser; if you clear it, the counter resets, exactly as it would on a brand-new browser.

“No cap” means no cap on the number of explanations for personal use. It does not authorise bulk downloading, resale, redistribution or automated access, which are prohibited below. If we ever had to impose a technical ceiling to stop abuse, we would say so here before applying it.

Legal basis: Art. 76 BIS, sections IV, V and VII of Mexico's Federal Consumer Protection Law.

Nothing can be paid for yet. When it can, these are the rules — and we write them now so they bind us from day one.

As of this version there is no active payment gateway: we charge nothing, we store no card data, and there is no subscription running. The prices shown on the pricing page are indicative.

When the subscription goes live, we commit to the following, which is also what Mexican law has required since the amendment of 12 December 2025:

• Before charging you, you will see — prominently, not in fine print — the billing frequency, the exact amount and the date the charge will be made.
• Consent to the recurring charge will be an express act, separate from general acceptance of these terms. It will not sit inside a single box that accepts everything at once.
• If there is automatic renewal, we will notify you at least five calendar days in advance and you will be able to cancel with no penalty whatsoever.
• You will be able to cancel from your own account, immediately, with no phone call, no email to support, and no screen that tries to talk you out of it.
• Billing will be in US dollars through an intermediary acting as merchant of record. We never see or store your card details.
• Cancelling stops future renewals. You keep access until the end of the period you already paid for.

Note: If, as you read this, the subscription is already live and any of these rules is not honoured in the product, write to us: that is a mistake on our side and we will fix it.

Legal basis: Art. 76 BIS, sections VIII and IX of Mexico's Federal Consumer Protection Law, added by the decree published in the Official Gazette on 12 December 2025. For subscribers in the United States, the Restore Online Shoppers' Confidence Act, 15 U.S.C. § 8403, and state automatic renewal laws, notably section 17602 of California's Business and Professions Code. We do not invoke the Federal Trade Commission's amended Negative Option Rule (16 CFR Part 425): it was vacated in full by the Eighth Circuit Court of Appeals on 8 July 2025, and the Commission reopened the rulemaking on 11 March 2026.

When we link a book there may be a commission involved. It doesn't change what you pay, and it doesn't change what we write.

On each book's page we include links to buy it on Amazon and other bookstores. These links are, or will be, affiliate links: if you buy through them, Pareto Learn may earn a commission from the store. The price you pay is exactly the same as if you had gone there yourself.

The real state of things as of this version: Amazon's affiliate programme has not been approved yet and the links carry no commission identifier, so today we earn nothing from them. This disclosure switches on the same day that identifier goes into production, which is why it is already written.

What never changes: which books we choose to analyse, and what we say about them, does not depend on whether they generate a commission. The explanations are not sponsored by publishers or authors, and we do not accept payment to cover a title or to speak well of it. If we ever published paid content, it would be visibly labelled as such.

Clicking takes you off our site. What happens after that — prices, availability, shipping, returns and how your data is handled — is that store's responsibility and governed by its own terms.

Legal basis: Art. 32 of Mexico's Federal Consumer Protection Law, which prohibits partial or slanted information. The form of the disclosure follows PROFECO's Advertising Guide for Influencers of August 2023, which is voluntary and not an obligation; the obligation is not to mislead.

The text and the design are ours. You may read and quote them; you may not copy them wholesale or use them to train models.

All Pareto Learn content — the explanations, the cover illustrations, the design and the code — belongs to Álvaro Hernández and the other partners who produce it, or is used with permission, and is protected by Mexico's Federal Copyright Law. Pareto Learn is not yet a company, so it cannot own anything in its own right: once the operating company is incorporated, those rights will be assigned to it and we will say so here. “Pareto Learn” is used as the project's trademark, but the right to exclusive use of a mark arises only from registration with the Mexican Institute of Industrial Property, under art. 170 of the Federal Law for the Protection of Industrial Property; until we publish that registration here, we claim no protection beyond copyright.

We grant you a personal, limited, revocable and non-transferable licence to read and use the content for personal, non-commercial purposes. You may quote short excerpts with attribution and a link, as anyone would when commenting on a text.

Note: Book titles, author names and the trademarks of the linked stores belong to their respective owners and are mentioned solely for identification and commentary.

Legal basis: Arts. 11, 13 section I, 14 section I, 27 and 148 of Mexico's Federal Copyright Law.

• Do not try to access parts of the service or other people's data without authorisation.
• Do not deliberately overload the infrastructure or interfere with how it runs.
• Do not use the service for anything unlawful or to infringe third-party rights.
• Do not impersonate anyone or give false information when signing up.

We are a young product. There can be outages, and the catalogue changes.

We make reasonable efforts to keep the service available, but we do not guarantee it will run without interruption or error. There may be maintenance, incidents at our providers, and periods of unavailability.

We may add, change or withdraw explanations and features, and only for these reasons: adapting the service to a new technical environment or to a larger number of users, fixing errors or protecting its security, changing provider, or ceasing to publish a title where a rightsholder asks us to or where publishing it is no longer viable. None of those changes will cost you anything. If we withdraw content you were reading, your progress in it may become meaningless. Where a change adversely affects your access to the service or your use of it, and that effect is not minor, we will inform you by email — a durable medium — a reasonable time in advance, telling you what is changing and when: from that notice you may terminate the contract free of charge within the thirty calendar days following the notice or the change, whichever is later. If we can let you carry on with the content unchanged and at no extra cost, we will offer you that, and then there will be no need to terminate. This applies whether your account is free or you hold a subscription; if it was a paid one, the unused proportional part is also refunded.

The service is provided “as is”. To the extent the law allows, we offer no warranties beyond those the law imposes on us, and we do not warrant that the content is free of errors. If you reside in the European Union or the European Economic Area, that sentence takes nothing away from you: the service must be fit for the purposes a service of this type is normally used for and have the qualities you can reasonably expect, and we do not exclude that.

To the extent the law allows, we are not liable for indirect damages, loss of profit or loss of data arising from use of the service. Also to the extent the law allows: where we are liable, our total liability is capped at what you have paid us in the twelve months before the triggering event and, if you have paid us nothing, at one hundred US dollars. That cap does not apply to you if you contract as a consumer in Mexico: Mexican law treats as unwritten any standard-form clause that releases the supplier from civil liability, and a cap like this one is a partial release, so there it is treated as unwritten and we answer under that law.

None of the above limits the rights the law grants you as a consumer that cannot be waived by contract, nor our liability for wilful misconduct or for harm to life or personal integrity.

Legal basis: Arts. 1, 85 (final sentence) and 90, sections II and VI of Mexico's Federal Consumer Protection Law; art. 2117 of Mexico's Federal Civil Code.

Legal basis: Arts. 76 BIS sections III, IV and V, 85 and 86 of Mexico's Federal Consumer Protection Law; arts. 6(1)(h) and (k), 9, 11(1) and 16(m) of Directive 2011/83/EU.

There are two kinds of email. Transactional ones — confirming your sign-up, resetting your password, warning you about a renewal or a change to these documents — are part of the service and you cannot unsubscribe from them while you have an account.

Promotional ones, if we ever send them, will always carry a visible way to unsubscribe and a valid physical postal address of ours, and we will honour that unsubscribe: we act on it immediately, without using up the ten business days US law allows for processing it. If the message goes to someone who did not ask for it, it will also be identified as an advertisement. We also do not send advertising to anyone who has told us they don't want it, or who is listed on Mexico's public advertising exclusion register.

Legal basis: Arts. 18, 18 BIS and 76 BIS section VI of Mexico's Federal Consumer Protection Law. For recipients in the United States, 15 U.S.C. § 7704(a)(3), (a)(4) and (a)(5) — the CAN-SPAM Act — and its implementing rule, 16 CFR part 316.

How your personal data is handled is described in the privacy notice, which forms part of these terms.

On the technical security elements, in general terms: all traffic between your browser and the service is encrypted with TLS; passwords are stored as a cryptographic derivation and never in the clear; database access is restricted by row-level security rules that deny by default; and we store no payment card data, because billing will be processed by a specialist intermediary.

The information you give us is treated confidentially and is not disclosed to providers unrelated to the transaction, unless you expressly authorise it or a competent authority requires it.

Legal basis: Art. 76 BIS, sections I and II of Mexico's Federal Consumer Protection Law.

These terms are governed by Mexican federal law and, for any dispute, the parties submit to the competent courts of Guadalajara, Jalisco, Mexico. That submission does not apply if you are a consumer resident in the European Union or the European Economic Area: in that case you may sue us in the courts of your own domicile as well as in the Mexican ones, and we may sue you only in the courts of your domicile. Nor can the choice of Mexican law deprive you of the protection afforded by the mandatory rules of your country of habitual residence.

That does not stop you from going to PROFECO if you are a consumer in Mexico, or from relying on the mandatory consumer protection rules of your country or state of residence, wherever you live. Where those rules cannot be waived by contract, they prevail over the governing law, the forum and the liability caps agreed in these terms.

These terms are published in Spanish and in English. The Spanish version governs for consumers in Mexico, because art. 85 of Mexico's Federal Consumer Protection Law requires it for standard-form contracts: a legal requirement, not a preference. If you contracted in English from outside Mexico, the English version governs. Both versions are published and updated at the same time; if you find a discrepancy between them, write to us and we will fix it.

Note: Those European rules — art. 6 of the Rome I Regulation and arts. 17 to 19 of the Brussels I bis Regulation — only bite where the trader directs its activity to the consumer's country, and in the privacy notice we explain why it is debatable that we direct ours to the European Union. We do not hide behind that doubt: we give up arguing it and grant you the courts of your own domicile anyway.

Legal basis: Art. 85 of Mexico's Federal Consumer Protection Law, which requires standard-form contracts to be written in Spanish; arts. 83, 90(2) and 90(3) of Spain's consolidated Consumer Protection Act; art. 6 of Regulation (EC) No 593/2008, Rome I; arts. 17 to 19 of Regulation (EU) No 1215/2012, Brussels I bis.

We may publish new versions of these terms. When we do, we will update the date above, publish the new version on this page, and keep the previous one so you can compare them.

A substantial change — one that affects your obligations or what you receive — is a proposal, not something imposed on you. If you have an account, we will tell you by email at least thirty calendar days in advance and spell out what changes. It binds you only if you accept it. If you are a consumer in Mexico, your silence is not acceptance: the law bars us from changing the contract by our own will alone, and we are not going to try.

Legal basis: Arts. 85 and 90, section I of Mexico's Federal Consumer Protection Law. Art. 90, section I treats as not written any clause in a standard-form contract that lets the provider unilaterally change the content of the contract or withdraw from its obligations. That is why a substantial change is proposed to you, not imposed on you, and why your silence does not make it yours.

For any question, complaint or clarification about these terms, write to contact@paretolearn.com.