CSP writes of his many undertakings in science, ranging from chemistry to the history of science. He speaks of his own natural powers of mind as "rather below than above mediocrity," but mentions that his three strongest points have been "self-criticism, persistence, and logical analysis."
Autobiographical references, Logic (modal see Modality), Meaning
pp. 1-4 (for p. 5, see MS. 632)
(Meaning Preface to the Volume)