Sentence:  Argiento had been trained so rigorously by the Jesuits that Michelangelo was <WSD>unable</WSD> to change his habits : up before dawn to scrub the floors , whether they were dirty or not ; water boiling on the fire for washing laundry every day , the pots scoured with river sand after each meal . 
Meaning of the word marked with <WSD> tags:  (usually followed by `to') not having the necessary means or skill or know-how