What a nice word we have here.
What does the dictionary tell us about it? I insist on using the dictionary so that the reader realizes that I am not making anything up.

Before looking at this famous book, I will simply say that it is about greatness of soul, from the Greek 'megalopsychia'. Aristotle wrote: "A person is considered to have a great soul if he claims much and deserves much".
A certain W.D. Ross translated Aristotle as follows: Pride [megalopsychia] seems therefore to be a kind of crown of the virtues; for it makes them greater, and is not found without them.

It would seem that to love to learn is to be close to knowledge, while to practice vigorously is to be close to magnanimity.

This word is also  means generosity, mercy towards the weak, the defeated. We also speak of noble feelings.

Curiously Magna means a pasty mush and Magnat means a member of the high nobility. So no connection.

François de La Rochefoucauld is well known for his maxims: here's one among others: "Magnanimity is a noble effort of pride by which it makes man master of himself in order to make him master of all things."
I sometimes ask why this experience doesn't come up more often. Yes, I will have this pleasure of feeling magnanimous when the opportunity arises. What could be more noble than to do good around you, even if it is not appreciated as you would have wished.

Let's look around us and see how people act towards each other. It is unfortunate to think that this famous magnanimity is not always present.
Why is this so? Indifference! That awful vice that haunts us all.

Moreover, Democritus said it before me: It is thanks to magnanimity that we support with calm the lack of tact. Indeed, the latter is often rare, but we must live with it.

Many philosophers who have studied this subject have had much to say about magnanimity, the object of which is to strengthen man against discouragement and to moderate the desire to achieve great things. As for the movement of pity, it comes from our tenderness and admiration before greatness and magnanimity.

I will end with this little Sufi proverb: Magnanimity consists in doing justice and not asking for justice.