How did The Problem of Knowledge differ in tone from Language, Truth, and Logic?

In his 1956 work The Problem of Knowledge, A.J. Ayer moved away from the combative, manifesto-like tone that characterized his earlier, highly influential book, Language, Truth, and Logic (1936).12

While Language, Truth, and Logic served as a rigorous and polemical defense of logical positivism—famously dismissing metaphysical discourse as literally meaningless—The Problem of Knowledge adopted a quieter, more measured approach to skepticism. In this later work, Ayer examined various philosophical theories of knowledge as responses to the radical skeptic, rather than attempting to reduce all meaningful propositions to sense-data as he had previously done. Notably, he moved away from his earlier strict reductionism, acknowledging that constructions based on experience possess their own inherent validity and cannot always be fully translated into the language of the senses.12