“Reality, according to Heisenberg, is built not out of matter, as matter was conceived of in classical physics, but out of psycho-physical events – events with certain aspects that are described in the language of psychology and with other aspects that are described in the mathematical language of physics – and out of objective tendencies for such events to occur. ‘The probability function…represents a tendency for events and our knowledge of events’ (Heisenberg, 1958, p. 46).”