Knowledge is invariably a matter of degree: you cannot put your finger upon even the simplest datum and say this we know.

The remark treats knowledge not as a set of perfectly secure, self-contained facts but as something graded, provisional, and dependent on context and interpretation. Even what seems like a “simplest datum” cannot be isolated from the assumptions, methods, and language that make it intelligible; certainty is therefore never absolute. The quote aligns with a broadly skeptical or fallibilist view of epistemology: what we call knowing is always a matter of confidence, evidence, and degree rather than an on/off state. It also implicitly challenges positivist ambitions to ground thought on indubitable “givens,” suggesting that inquiry proceeds through approximations rather than final foundations.