“All London knows how I stand now.  They will not try again to bribe me.  The displeasure of Sir Benjamin will react upon you.”

“What shall I do if he continues to be obdurate?”

“Shove my table this way and I’ll show you a problem in prudential algebra,” said the philosopher.  “It’s a way I have of setting down all the factors and striking out those that are equal and arriving at the visible result.”

With his pen and a sheet of paper he set down the factors in the problem and his estimate of their relative value as follows: 

The Problem.

A father=1 Margaret, her mother and Jack= 3+ 1
A patrimony=10 Happiness for Jack and Margaret= 100+ 90
Margaret’s old friends=1 Margaret’s new friends= 1
A father’s love=1 A husband’s love= 10+ 9
A father’s tyranny=-1 Your respect for human rights= 5+ 6
-------
106

[Transcriber’s note:  In the original printed book, some of the words in this table have slashes (strike-outs) through them, and are not renderable in text format.  At the end of the HTML version of this book is an image of the table, showing these strike-outs.]

“Now there is the problem, and while we may differ on the estimates, I think that most sane Americans would agree that the balance is overwhelmingly in favor of throwing off the yoke of tyranny, and asserting your rights, established by agreement as well as by nature.  In a like manner I work out all my important problems, so that every factor is visible and subject to change.

“I only fear that I may not be able to provide for her in a suitable manner,” said Jack.

“Oh, you are well off,” said the philosopher.  “You have some capital and recognized talent and occupation for it.  When I reached Philadelphia I had an empty stomach and also a Dutch dollar, a few pennies, two soiled shirts and a pair of dirty stockings in my pockets.  Many years passed and I had a family before I was as well off as you are.”

Dinner was brought in and Jack ate with the Doctor and when the table was cleared they played with magic squares—­an invention of the philosopher with which he was wont to divert himself and friends of an evening.  When Jack was about to go, the Doctor asked: 

“Will you hand me that little red book?  I wish to put down a credit mark for my conscience.  This old foot of mine has been rather impudent to-day.  There have been moments when I could have expressed my opinion of it with joyous violence.  But I did not.  I let it carry on like a tinker in a public house, and never said a word.”

He showed the boy an interesting table containing the days of the week, at the head of seven columns, and opposite cross-columns below were the virtues he aimed to acquire—­patience, temperance, frugality and the like.  The book contained a table for every week in the year.  It had been his practise, at the end of each day, to enter a black mark opposite the virtues in which he had failed.