Decision Fatigue and the Illusion of Consent in Contract Law: A Comparative Study of the Cognitive Limits of Consent in International Contract Law and European Union Contract Law

Document Type : Original Article

Authors
Hosein Aminian Joonaghani 1
Panteha Dabaghpoor 2
Mansour Amini 1
1 Private Law Department, Faculty of Law, Shahid Beheshti University, Tehran, Iran
2 Institute for Cognitive Sciences and Brain, Shahid Beheshti University, Tehran, Iran
10.22047/hsd.2026.568193.1122
Abstract
Contract law traditionally equates a signature or click with free, informed consent. Neuroscience, however, challenges this view, showing that time pressure, decision sequences, and cognitive depletion impair judgment, leading to impulsive or passive agreement. Consequently, apparent consent may be cognitively hollow—a product of mental fatigue rather than genuine intent.

This interdisciplinary, comparative study analyzes how international and EU contract law address these limitations. It evaluates instruments like the CISG, UNIDROIT Principles, PECL, DCFR, the Electronic Communications Convention, and the EU Consumer Rights Directive, framing decision fatigue as a “situational vulnerability.” When knowingly exploited, this vulnerability should activate legal safeguards.

The article explores three issues: interpreting consent within its cognitive context; assessing validity and fairness using doctrines against exploitation; and advocating proportionate remedies (e.g., adjustment, cooling-off periods) over a binary enforce/avoid approach. Applying this framework to consumer and employment contracts reveals fatigue as a subtle driver of inequality. Ultimately, integrating decision psychology into consent doctrine does not weaken contractual freedom—it fortifies genuine will and protects meaningful consent. (Approx. 190 words)
Keywords
Illusion of Consent
Situational vulnerability
Freedom of Will
Good Faith
Cognitive Fatigue
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Development of humanities
Volume 7, Issue 13 - Serial Number 13
Humanities
Volume 7, Spring and Summer 2026, No. 13
October 2026
Pages 171-190

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