All knowledge is conceptual and systematic, but if being cannot enter a system, then contemplation remains on the edge of knowledge, attentive to what exceeds this knowledge. There is a never-ending dialogue between being as something non-deductible and reason as a power of systematisation, but this dialogue is thought itself, and silence is a moment in this exchange. At least, silence which is not the absolute negation of being, its contrary, pure nothingness, but non-being as a relative negation of being, the other of being, opening within being the possibility of articulations and multiple relations.
Solère, J.-L. (2005). Silence et philosophie. Revue Philosophique de Louvain, 103(4), 613-637. https://doi.org/10.2143/RPL.103.4.2003548 (Original work published 2005)