It has been argued that the ΛCDM model ishas built upon a foundation ofadopted [[conventionalism|conventionalist stratagems]], rendering it [[falsifiability|unfalsifiable]] in the sense defined by [[Karl Popper]]. When faced with new data not in accord with a prevailing model, the conventionalist will find ways to adapt the theory rather than declare it false. Thus dark matter was added after the observations of anomalous galaxy rotation rates. [[Thomas Kuhn]] viewed the process differently, as "problem solving" within the existing paradigm.<ref>{{Cite journal | doi=10.1016/j.shpsb.2016.12.002| title=Cosmology and convention| journal=Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics| volume=57| pages=41–52| year=2017| last1=Merritt| first1=David| arxiv=1703.02389| bibcode=2017SHPMP..57...41M| s2cid=119401938}}</ref>
