We cannot be bound beyond what we are able to perform, by reason that effect and performance are not at all in our power, and that, indeed, we are masters of nothing but the will, in which, by necessity, all the rules and whole duty of mankind are founded and established
 Michel de Montaigne, The Essays of Michel de Montaigne (1580). copy citation

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Author Michel de Montaigne
Source The Essays of Michel de Montaigne
Topic duty power
Date 1580
Language English
Reference
Note Translated by Charles Cotton
Weblink http://www.gutenberg.org/files/3600/3600-h/3600-h.htm

Context

“earnestly entreated that he might first mount the scaffold, to the end that death might disengage him from the obligation he had passed to the other. In which case, methinks, death did not acquit the former of his promise, and that the second was discharged from it without dying. We cannot be bound beyond what we are able to perform, by reason that effect and performance are not at all in our power, and that, indeed, we are masters of nothing but the will, in which, by necessity, all the rules and whole duty of mankind are founded and established: therefore Count Egmont, conceiving his soul and will indebted to his promise, although he had not the power to make it good, had doubtless been absolved of his duty, even though he had outlived the other;” source