Medical ethicist, Guidry-Grimes has critically reviewed the concept of insight, voicing concerns that it lacks consensus as to its components and that it undermines patient perspectives. We respond by briefly summarising research over the last 30 years that she overlooks which has helped establish the clinical validity of the construct. This includes the adoption of standardised assessment tools—at least in research—and longitudinal and cross-sectional studies quantifying associations with psychopathological, clinical and cognitive measures. We also make the distinction between the current standards for assessing decision-making capacity leading to, where appropriate, involuntary treatment in clinical and medico-legal settings which in most legislations do not include insight assessments, and anecdotal reports of the use and misuse of ‘lack of insight’ as a proxy for more comprehensive evaluation. We conclude by encouraging a broader view of insight akin to self-knowledge.