 Citing Mill, Neurath noted that empiricism brings the natural and the social sciences together, but so do some of its limits. The markers of empirical science are the practices of observation, experimentation and prediction. Laws are merely vehicles for taking us from the concrete and unique to the concrete and unique, whether in biology or history. Sociology is like geology and biology in that the possibility of many experiments is prevented by certain constraints of ethical values or scale (ibid., 365). Predictability is characterized by nine conditions. It is based on (1) the availability of generalizations about groups and (2) stable conditions, or control, and for a limited period. Control is a key notion that connects empiricism and engineering, mechanical and social. Neurath didn’t think that laws of physics, for instance, are in that sense more universal or unconditioned: ‘Mariotte’s law in physics holds only within certain limits’ (ibid., 331). (3) Correlations on which predictions are based are the product of induction, and inductive conclusions, in sociology as elsewhere, are based on a decision (Neurath 1931b/1973, 407). (4) Moreover, sociology, like the natural sciences, often has recourse to information, including laws, from other disciplines, in a local synthetic effort of predictive value (ibid., 364). (5) Holism prevents sociology from the ‘ideal forecast’ associated with the fiction of the Laplacean mind and the availability of molecular descriptions of individuals free from instabilities (in a symposium on Pasqual Jordan’s quantum mechanics, Neurath addressed the new perspective from quantum mechanics on the problem of free will and its conflict with the determinism (causality) of natural laws as riddled with metaphysics (Neurath 1935)). One may not expect, however, that aggregations or complexes will be always more predictable than individuals, since the evolution of the complex might depend on the interaction with individuals and the environment in a way affected by chance. Instead, it has to make do with ‘rough facts of a complex character’ (ibid., 405) in a ‘system of entangled habits’ (ibid., 371 and 374), and most social types of behavior in a group are not ‘autonomously computable’ and have to be regarded as ‘parts of the complex that is being investigated at the time’, considering ‘the whole of life’ of the group, since each ‘historical period = non-analysed complex of conditions’ (Neurath 1932a/1983, 76 and 85); he would subsequently speak of aggregations (Neurath 1944a). Any resulting prediction or explanation (retrodiction) of individual behavior is an approximation to a ‘world history without names’. (6) A linguistic implication is that empiricism in general and the social sciences in particular are dependent on non-univocal, indistinct terms—‘a “clot” (German Ballung, French grégat)’—, in both protocol statements (see above) and theories insofar as they are sensitive to cultural phenomena and historically inherited concepts that cannot be usefully replaced with precise technical terms of the ‘modern international folklore’ (Neurath 1944a, 5–7, 18). (7) The ‘multivocality’ of the relation between phenomena and theoretical interpretations is more pervasive than the sort of pluralism Duhem noted in physics, and leads Neurath to speak of ‘pluri-items’ (ibid., 14). (8) Certain phenomena or entities such as inventions can only be predicted provided one has also the means to create them (Neurath 1931b/1973, 405); this insight is typically attributed to the critic of Neurath Popper, who published it much later. (9) Sociological predictions are co-determinants in the occurrence of the predicted event, for instance a position in the stock market or a political revolution (ibid., 405); the prediction may have a reinforcing or a preventive character (he wrote about self-fulfilling prophecies as early as 1921, in his polemic against Spengler; Neurath 1921). Theory becomes part of practice; scientist becomes part of the social scene (ibid., 406).