Chapter Logical Positivism Iwant neither that pluto cracy grasping and mean nor that demo cracy go o dy and medio cre o ccupied solely in turning the other cheek where would dwell sages without curiosity who shunning excess would not die of disease but would surely die of ennui Poincare quoted in Runes ToP p Science itself therefore may b e regarded as a minimal problem consisting of the completest p ossible presentment of facts with the least possible expenditure of thought Mach Newman WMVol p Historical Background In this chapter wewilllookat logical positivism the most inuential philosophy of science in the twentieth century In spite of the fact that logical p ositivism has b een abandoned by most philosophers of science its inuence continues in many disciplines including physics linguistics and psychologyWe will b e esp ecially concerned with logical p ositivisms view of knowledge which is roughly the only real CHAPTER LOGICAL POSITIVISM knowledge is scientic knowledge by a pro cess of logical analysis scientic knowledge can b e reduced to symb olic formulas constructed from atomic facts Certainly assertion is nothing new So crates said as much when he distinguished scientic knowledge episteme from a practice empeiria see Section Furthermore assertion is implicit in Pythagorianism and is a continuous theme in most Western epistemology from Plato and Aristotle through Hobb es and Leibnitz to Bo ole and Hilb ert In this sense logical p ositivism is just the continuation of this long tradition The ma jor innovation of logical p ositivism follows from a new under standing of scientic knowledge and in the resulting view of the atomic constituents of knowledge Throughout most of these years sci entic knowledge was viewed rationalisticallyanditwas assumed that the atomic constituents were some kind of selfevident axioms involving basic categories that required no denition However b eginning in the Renaissance there was a growing recognition of the value of observa tion and exp eriment activeintervention in nature and a corresp onding increase in scepticism ab out the self evidence of any prop osition In deed if empiricist philosophers were willing to grant selfevidence to anything it was to sense data rather than to the metaphysical prop o sitions favored by the rationalists In the past the ideal of knowledge had b een Euclidean geometry but the new empiricism to ok physics as its ideal Although logical p ositivism originated in Germany in the s a many of its ro ots are AngloAmerican First there is empiricism strong theme in British philosophybacktoDavid Hume Thomas Hobb es and Francis Bacon Second there is American pragmatism originated byCSPeirce William James and John Dewey with its em phasis on the observable consequences of actions Finally there was logical analysis strongly represented in the Continental idealist tradi tion but turned into a technical to ol by the British philosophers G E Mo ore and Bertrand Russell Logical p ositivism combined these AngloAmerican developments with the existing p ositivist tradition on the Continent which originated with the French philosopher Auguste Comte He argued that each branchofhuman understanding went through three stages HISTORICAL BACKGROUND in the theological stage explanations are based on the volition of go ds in the metaphysical stage explanations are based on abstract forces in the positive or scientic stage phenomena are not explained at all but are simply connected bylaws Comte says FinallyinthePositive state the human mind recogniz ing the imp ossibility of obtaining absolute truth gives up the search after the origin and destination of the universe and a knowledge of the nal causes of phenomena It only endeavors nowtodiscover bya wellcombined use of rea soning and observation the actual laws of phenomena that is to say their invariable relations of succession and likeness quoted in Runes ToPp The famous French mathematician and philosopher Jules Henri Poincare applied p ositivist ideas to physics and was con cerned with the construction of basic physical concepts out of our sen sations and p erceptions In this way he prepared the way for Einsteins reconstruction of space time and gravity in his sp ecial and general relativity theories see p The Austrian physicist Ernst Mach to ok a very sim ilar view and argued that the laws of physics as of all the sciences are just shorthand summaries of relationships b etween the observers exp eriences y It is the ob ject of science to replace or save exp eriences b the repro duction and anticipation of facts in thought This economical oce of science which lls its whole life is apparent at rst glance and with its full recognition all mysticism in science disapp ears Every scientic law and concept mass energy atoms must b e reduced to relations b etween observable quantities These in turn are relationships among sense data Prop erly sp eaking the world is not comp osed of things as its elements but of colors tones pressures spaces times in short what we ordinarily call individual sensations A relevant selection from Machs ScienceofMechanics from whichthese quotations are taken is reprinted in Newman WMVol pp CHAPTER LOGICAL POSITIVISM This view led Mach to detailed investigations of sensation and p ercep tion for example in his Space and Geometry he carefully distin guishes the space of physics from the physiological space up on which its based and in the latter category he analyzes the space of vision and the space of touch which of course are not the same These analyses formed a starting p oint for Einsteins relativitywork p Muchlike Comte Machsaw science as an advance over metaphysics Where neither conrmation nor refutation is p ossible science is not concerned He rejected anything not reducible to exp erience as not true knowledge a characteristic attitude of p ositivism and by reducing statements to exp erience he hop ed to exp ose the real sig nicance of the matter and get rid of metaphysical obscurities As Hume said long b efore If we take in our hand anyvolume of divinityorscho ol metaphysics for instance let us ask Does is contain any ab stract reasoning concerning quantity or number No Does it contain any experimental reasoning concerning matter of fact and existence No Commit it then to the ames for it can contain nothing but sophistry and illusion Enq Conc Human Underst sec pt In Mach b ecame a professor of physics at the University of Vi enna and with him we come to the do orstep of the Vienna Circle the fountainhead of the logical p ositivist movement However b efore we discuss it wemust consider imp ortantcontributions from the analytic tradition up on which the logical p ositivists also dep ended Logical Atomism Russell Knowledge by Acquaintance and Description In many resp ects logical p ositivism was motivated by the same desires for p erfect clarity and absolute certaintythathave driven muchofthe progress of epistemology from the time of Pythagoras The particular form that this quest has taken in the analytic traditionwhich has LOGICAL ATOMISM dominated AngloAmerican philosophy in the twentieth century and which includes logical p ositivism is the b elief that analysis can b e pursued down to certain indivisible elements which are in some way incorrigible and hence justify the intellectual edice constructed from them One form of this is the theory of logical atomism develop ed by Bertrand Russell in the rst decades of the twentieth century He distinguished know ledge by acquaintancewhich is indubitable from know ledge by description whichmay b e in error Examples of knowl edge by acquaintance are sense data and the contents of our own mem ory So for example if I were p erceiving a patchofyellow color in a certain place in my visual eld Russell would take that fact to b e unassailable though I could certainly b e incorrect in assuming that Im seeing a yellow ob ject since it could b e a hallucination I might have jaundice or b e wearing yellow sunglasses etc etc Similarly my memory that a certain p erson attended my fth birthdayparty might b e mistaken but I cannot b e mistaken in the fact of having that recollection A common logical fallacy is the use of descriptions to which nothing answers The classic example is the presentKingofFrance since France do es not have a king Therefore when I make an assertion such as the presentKingofFrance is bald it is neither true nor false since it is not an assertion ab out anything Suchknowledge by description is fallible since it contains descriptions that mayfailin their reference that is they do not refer to anything In contrast an ob ject of acquaintance acts likea logical ly proper name and cannot fail in its reference by virtue of my p erceiving it the sp ot of yellowIm The logical atomism of Russell diers from that of Leibnitz p in that the former is empirical whereas the latter is rationalistic though interestingly b oth to ok the self to b e an elementary given Sources for this section include Russell LA and Russell PLA The pitfalls of reference are illustrated by the fo otnoted sentence for had I said they refer to nothing it mighthave implied that there is a thing Nothing to which descriptions refer when nothing else answers the description We could then make a career out of investigating the prop erties of this Nothing Indeed Alexis Meinong did precisely that since he gave a kind of logical realitytoany intentional object that is any ob ject of consciousness Consideration of Meinongs work led Russell