But during the last few years there has grown up another kind of opposition as well, among people who, in their own opinion at all events, take their stand upon the ground of analysis, who do not dispute its techniques or results, but who merely think themselves justified in drawing other conclusions from the same material and in submitting it to other interpretations.
As a rule, however, theoretical controversy is unfruitful. No sooner has one begun to depart from the material on which one ought to be relying, than one runs the risk of becoming intoxicated with one's own assertions and, in the end, of supporting opinions which any observation would have contradicted. For this reason it seems to me to be incomparably more useful to combat dissident interpretations by testing them upon particular cases and problems.”
― Sigmund Freud, The 'Wolfman'
