“A branch of human natural history”: Wittgenstein’s Reflections on Metrology Martin Kusch “To resolve these philosophical problems one has to compare things which it has never seriously occurred to anyone to compare.” (Ludwig Wittgenstein) 1. Introduction Two texts provide the inspiration for this paper. The first is a short passage from one of Ludwig Wittgenstein’s notebooks, written in 1947. In this passage Wittgenstein advocates a certain form of “methodology”: “a description of the activities called ‘measuring’, a branch of human natural history that helps us understand the concepts of measurement, precision, etc. in all their variants ...” (2000: 135-129 [August 1 st , 1947]) This paper is an attempt to determine what this “methodology” amounts to, and what Wittgenstein himself contri- buted to it. The second source of inspiration is Bas van Fraassen's book Scientific Represen- tation (2008). Van Fraassen seeks to develop and defend a "constructive-empiricist form of structuralism”. This form of structuralism gives room to agency or subjectivity, indexicality and contingency. van Fraassen pursues his aim primarily through a reconsideration of the metrological “problem of coordination” in both its local and its global forms. His analysis culminates in the claim that it needs a “Wittgensteinian” insight to solve these problems. Given that Wittgenstein does not play a central role in contemporary philosophy of metrology, van Fraaassen’s reference is noteworthy and intriguing. The second aim of my