American realism at Columbia, his legal realism being influenced by the German ‘free law’ movement;
realism provides the post-hoc (after the event) rationalisation for legal decisions made by judges on whatever their theoretical reasoning might have been;
law is ‘indeterminate’, i.e. in reaching a novel decision the existing law could not provide a justification or explanation;
in practice it means that a judge usually has the discretion or ability to distinguish previous decisions, or to apply them in the instant case, in either case by using legitimate arguments and reasons;
2. Llewellyn took the ‘sociological’ line in emphasising the social forces that acted upon judges in reaching their decisions (as opposed to the ‘idiosyncratic’ tendency represented by Frank).