Looking back to the Rebirth of Positivism:
Psychology and The Golden Age of Behaviorism

 Edward Chace Tolman (1886-1959): Purposive behaviorism
Influenced by neo-realism and gestalt psychology

Purpose and hunger could be objectively observed

 Operational behaviorism examines the functional relationships between independent and dependent variables
 
  Intervening variables: Theoretical constructs representing hypothetical processes) which enable the prediction of dependent variables. Theoretically they are the link between stimulus and response, sometimes thought of as real causes. For example: B=fx(S,P,H,T,A) where s=stimuli, p=physiological drive, h=heredity, t=training, a=age

 Clark Leonard Hull (1884-1952): Mechanism & reductionism
Mathematization of psychology: "physics envy"

Quantifiable prediction and control are goals of psychology Underlying realism (in opposition to Mach & Bridgman)

 Hypothetico-Deductivism: "Explicitly stated postulates" derived from a theory provide testable predictions of that theory.

sEr = sHr x D x V x K - sIr - Ir
 
  The Birth of Experimentl Methods & Statistical Inference

 Ronald A. Fisher (1890-1962)

We can make inferences about the world through
an examination of the probabilities that our
experimental treatments are due solely to chance.

 Null Hypothesis: A statement that there is no difference between treatments and controls.
Rejecting the Null does not mean proof or verification of the experimental hypothesis, only a lack of falsification, although...

Commentary on positivism in Psychology

While we set up our experiments to test the null hypothesis - that there is no difference between the treatment groups we then turn to the alternate (Real) hypothesis and either reject or fail to reject it. This model of science is built on the notion of falsification (based upon probabilities), however, we have a very strong tendency to turn around and "accept" or "prove" our theories based upon the rejection of the null hypothesis. This is bad science according to Sir Karl Popper, and it represents the tendency towards positivism that we all are subject to.

Thus positivism is an attitude of acceptance of theories, ideas, truths based upon the confirmation established through observational methods.