信仰无差别论，或称冷淡主义，指认为所有的信仰都一样没有差别，相较于现代基督宗教（如天主教）主张包容其他宗教（包容主义），但本身则优于他者，信仰无差别论认为基督宗教和其他信仰，甚至和无神论都一样，不具有任何差别，采取一视同仁的态度。

Indifferentism, in the Roman Catholic faith, is the belief held by some that no one religion or philosophy is superior to another. The Catholic Church ascribes indifferentism to many atheistic, materialistic, pantheistic, and agnostic philosophies. There are three basic types of indifferentism described by Catholic apologetics: absolute, restricted, and liberal or latitudinarian indifferentism. Indifferentism was first explicitly identified and opposed by Pope Gregory XVI, in his encyclical Mirari vos.