[1] He was one of twelve children born to Catharine (née Barber) James and William James (1771–1832), an emigrant from Bailieborough, County Cavan, Ireland, to the United States around 1789, who amassed a fortune of about $1.2 million from business dealings in upstate New York State, primarily in Albany real estate, money lending, and his involvement with the building of the Erie Canal.

He studied at Princeton Theological Seminary from 1835 to 1837 to prepare for the ministry, but found himself disconcerted by "enormous difficulties which inhered in its philosophy," and abandoned the idea of becoming a minister.

Upon James's return to New York in 1838, he prepared an edition of Robert Sandeman's Letters on Theron and Aspasio, which has been called the principal literary document of a Scottish sect that opposed the Presbyterian Church.

But it was in the work of Emanuel Swedenborg (1688–1772), the Swedish scientist, religious visionary and teacher, that James found a spiritual home.

This experience was an apprehension of, in his own words, "a perfectly insane and abject terror, without ostensible cause, and only to be accounted for, to my perplexed imagination, by some damned shape squatting invisible to me within the precincts of the room, and raying out from his fetid personality influences fatal to life.

"[3] James's "vastation" initiated a spiritual crisis that lasted two years, and was finally resolved through the thorough exploration of the work of Swedenborg and Christian mystics.

James became convinced that, as he put it, "the curse of mankind, that which keeps our manhood so little and so depraved, is its sense of selfhood, and the absurd abominable opinionativeness it engenders."

[4] In the late 1840s, James became interested in the former members of Brook Farm, an experiment in communal living at West Roxbury, Massachusetts that lasted from 1841 to 1847, and in Fourierism, the school of utopian socialism that grew out of the thought of French social philosopher Charles Fourier (1772–1837) and which was a major influence in the last several years of Brook Farm.

He held most of the leading writers of his day in low regard, with the possible exception of Walt Whitman, though he met and cultivated many of them, including Emerson, Bronson Alcott, Henry David Thoreau, and William Makepeace Thackeray.

True reality (or God) is, in James's view, thoroughly spiritual, in a way that denizens of the natural world can scarcely comprehend.

But through intuition of this true reality, James thought, liberation from the illusions of natural appearances—which include time, space, and selfhood—is possible.

For, of course, it is not by a gift of turkeys on Thanksgiving Day that he proposes to convert the criminal, but by a true sympathy with each one,—with him, among the rest, who lying tells the world from the gallows that he has never been treated kindly by a single mortal since he was born.

[6] On July 28, 1840, James was married to Mary Robertson Walsh (1810–1882), the sister of a fellow Princeton seminarian, by the mayor of New York, in his bride's house on Washington Square.

[19] Under the terms of his will, Wilkie received a smaller share of the estate than his siblings, because his father felt that he had advanced enough money to him in his lifetime which had been lost in failed business ventures.

However, Henry, Alice and Bob felt badly about Wilkie, who suffered from a heart condition and rheumatic fever after injuries incurred in the Civil War, so they decided to redistribute the estate equally.

William strongly disagreed with this, arguing that it was easier for Alice and Henry to forfeit a larger share of the estate to Wilkie because they did not have families of their own to support.