“Susceptibility to the highest forces is the highest genius; selection between them is the highest science; their mass is the highest educator. Man always made, and still makes, grotesque blunders in selecting and measuring forces, taken at random from the heap, but he never made a mistake in the value he set on the whole, which he symbolized as unity and worshipped as God.”

1870s, Society and Solitude (1870), Quotation and Originality

We The Living (1936)
Source: We The Living Last Page

Source: De potentia (c. 1265–1266) q. 7, art. 5, ad 14

A Few Thoughts for a Young Man (1850), p. 65
Context: He who cannot resist temptation is not a man. He is wanting in the highest attributes of humanity.

As quoted in A Dictionary of Thoughts : Being a Cyclopedia of Laconic Quotations from the Best Authors, Both Ancient and Modern (1891) edited by Tryon Edwards. p. 327.
1890s and attributed from posthumous publications

Fragments of Markham's notes
The Nemesis of Faith (1849)
Context: It is an old remark, that as men are, such they paint their gods; and as in themselves the passionate, or demonic nature, long preponderated, so the gods they worshipped were demons like themselves, jealous, capricious, exacting, revengeful, the figures which fill the old mythologies, and appear partly in the Old Testament. They feared them as they feared the powerful of their own race, and sought to propitiate them by similar offerings and services.
Go on, and now we find ourselves on a third stage; but now fast rising into a clearing atmosphere. The absolute worth of goodness is seen as distinct from power; such beings as these demon gods could not he the highest beings. Good and evil could not coexist in one Supreme; absolutely different in nature, they could not have a common origin; the moral world is bipolar, and we have dualism, the two principles, coeternal, coequal.
By and by, again, the horizon widens. The ultimate identity of might and right glimmers out feebly in the Zenda Vesta as the stars come out above the mountains when we climb out of the mist of the valleys. The evil spirit is no longer the absolute independent Ahriman; but Ahriman and Ormuzd are but each a dependent spirit; and an awful formless, boundless figure, the eternal, the illimitable, looms out from the abyss behind them, presently to degrade still farther the falling Ahriman into a mere permitted Satan, finally to be destroyed.

Sādhanā : The Realisation of Life http://www.spiritualbee.com/spiritual-book-by-tagore/ (1916)
Context: Man is not entirely an animal. He aspires to a spiritual vision, which is the vision of the whole truth. This gives him the highest delight, because it reveals to him the deepest harmony that exists between him and his surroundings. It is our desires that limit the scope of our self-realisation, hinder our extension of consciousness, and give rise to sin, which is the innermost barrier that keeps us apart from our God, setting up disunion and the arrogance of exclusiveness. For sin is not one mere action, but it is an attitude of life which takes for granted that our goal is finite, that our self is the ultimate truth, and that we are not all essentially one but exist each for his own separate individual existence.