Even scientific knowledge, if there is anything to it, is not a random observation of random objects for the critical objectivity of significant knowledge is attained as a practice only philosophically in inner action.

The sentence contrasts mere data-gathering with what Jaspers takes to be genuine “knowledge.” Scientific knowing, on this view, is not simply the accumulation of detached observations; it depends on disciplined methods, criteria of relevance, and a stance of critical objectivity. Jaspers adds that this objectivity is not achieved automatically by looking harder at “objects,” but through an “inner action”: reflective self-clarification about aims, presuppositions, and meaning. In other words, science requires philosophical practice—an active, inward work of critique and orientation—if it is to yield “significant” knowledge rather than a heap of facts. The quote fits Jaspers’s broader insistence that philosophy safeguards the conditions and limits of scientific reason.