What's "Mormonism"?

Please see President David O. McKay's teaching:
“Mormonism,” as true Christianity, “subdues selfishness, regulates the passions, subordinates the appetites, quickens the intellect, exalts the affections. It promotes industry, honesty, truth, purity, kindness. It humbles the proud, exalts the lowly, upholds the law, favors liberty, is essential to it, and would unite men in one great brotherhood.”
I am reading Chapter 4 and 16 ......