This paper develops a dialogue on value and measurement in education that began at a special symposium at ECER in September 2015. The paper seeks to continue the dialogue by commenting on the main respondent's contribution from Network 9. We hope to clarify how different sides of the assessment debate can be misunderstood by others. What emerges in our paper is suggestive but nonetheless points to how thinking in opposing camps can limit our understanding of assessment as a human activity. Taking up key points made by the respondent to the symposium, we focus on the comparison between the requirements of design in technological problem-solving situations and those that arise when we take seriously the requirements of assessment and valuing as a human activity. This discussion sets up a wider analysis of the problem of ethics across the sciences and humanities historically. While remaining tentative, the discussion points to a particular problem related to our ability to defend practical rationality against the dominance of technical rationality in modern European society. As a way of counteracting the preponderance of more technical measures, the paper concludes by offering a heuristic metaphor for understanding an unquantifiable living practice like education.