text:  And if while it be allowed as I am sure it must that though I do well to speak as I think it be observed that this is not a reason why I should think as I do--that is so presumptuously--I beg to reply that if I had never _thought so_ this discovery had never been attempted and much less made; for notwithstanding what the world may say about the modesty of certain great men I do in my heart believe that such modesty has been ever affected and that it is wholly impossible that any thing great may be undertaken or achieved but where there is at bottom great presumption which is after all nothing more than a consciousness of one's own strength