Full Idea
Positivism is the doctrine that the content of scientific propositions is exhausted by what can be immediately experienced.
Gist of Idea
Positivism says science only refers to immediate experiences
Source
Harré,R./Madden,E.H. (Causal Powers [1975], 2.I)
Book Reference
Harré,R/Madden,E.H.: 'Causal Powers: A Theory of Natural Necessity' [Blackwell 1975], p.28
A Reaction
The simple thing missing from positivism is inference to the best explanation. Also, if you actually rule out other propositions as 'meaningless', you rule out speculation, which would certainly cripple science.