“Opinion is ultimately determined by the feelings, and not by the intellect.”

Address to the Associated Press (20 April 1915)
1910s

Source: The Book of Disquiet

Possibly, but more likely derived from the Buddha: "All that we are is the result of what we have thought. The mind is everything. What we think, we become."
Source: Striking Thoughts (2000), p. 120; This probably derives from a Rosicrucian proverb, "As you think, so shall you become", which is itself probably derived from Proverbs 23:7 "As he thinketh in his heart, so is he."

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Lecture XX, "Conclusions"
1900s, The Varieties of Religious Experience (1902)
Context: Both thought and feeling are determinants of conduct, and the same conduct may be determined either by feeling or by thought. When we survey the whole field of religion, we find a great variety in the thoughts that have prevailed there; but the feelings on the one hand and the conduct on the other are almost always the same, for Stoic, Christian, and Buddhist saints are practically indistinguishable in their lives. The theories which Religion generates, being thus variable, are secondary; and if you wish to grasp her essence, you must look to the feelings and the conduct as being the more constant elements. It is between these two elements that the short circuit exists on which she carries on her principal business, while the ideas and symbols and other institutions form loop-lines which may be perfections and improvements, and may even some day all be united into one harmonious system, but which are not to be regarded as organs with an indispensable function, necessary at all times for religious life to go on. This seems to me the first conclusion which we are entitled to draw from the phenomena we have passed in review.

Source: What is Political Philosophy (1959), p. 91

"The Shashi Tharoor column: The creation of India," 2001