In Distinction and the Criticism of Beliefs, Sidgwick is concerned with establishing that “the validity of any distinction is relative to the purpose for which it is used at the time, or that the question whether a given distinction is valid can be decided only by reference to the purpose for which it is used on a special occasion.”
“Why should we be in so great a hurry to label ourselves, to profess our faith or unfaith? Who can say for certain what he believes, and with how much steadfastness? Who is there whose belief — as distinct from his creed — remains quite the same even from one year to another, on any subject except those where there is least interest or least difference of real opinion? Wherever insight is most wanted, there clouds and false lights most obscure and delude our vision.” (Alfred Sidgwick, 1892, Distinction and the Criticism of Beliefs).