“Eu consigo calcular o movimento dos corpos celestiais, mas não a loucura das pessoas.”
I can calculate the motions of the heavenly bodies, but not the madness of people.
Depois de perder uma fortuna em especulando na Companhia Mar do Sul, conforme citado no " The Damn'd Mar do Sul http://www.harvardmag.com/mj99/damnd.html" Harvard Magazine (maio / junho 1999)
Original
I can calculate the motions of the heavenly bodies, but not the madness of the people.
Such a statement is indicated as his response to a question regarding the financial fiasco known as the South Sea Bubble; the earliest mention of this famous anecdote appears to be from manuscripts of the Second Memorandum Book (1756) of Joseph Spence, first published in Anecdotes, Observations, and Characters, of Books and Men (1820) https://archive.org/details/anecdotesobserv00singgoog edited by in Samuel Weller Singer; a Lord Radnor is quoted as saying:
When Sir Isaac Newton was asked about the continuance of the rising of South Sea stock? — He answered, "that he could not calculate the madness of the people."
Variants:
I can calculate the motions of erratic bodies, but not the madness of a multitude.
As quoted in "Mammon and the Money Market", in The Church of England Quarterly Review (1850), p. 142 http://books.google.com/books?id=s_cDAAAAQAAJ&pg=PA142&dq=%22but+not+the+madness%22&hl=en&ei=nUtbTfuoCYG6ugPFi4n4DA&sa=X&oi=book_result&ct=book-preview-link&resnum=1&ved=0CCkQuwUwAA#v=onepage&q=%22but%20not%20the%20madness%22&f=false
I can calculate the motions of the heavenly bodies, but not the madness of people.
I can calculate the motions of heavenly bodies but not the madness of men.
I can calculate the movement of the stars, but not the madness of men.
Disputed
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“Não consigo mais voltar ao passado. Nem meu coração, nem meu corpo.”
Citações do diário

Affection, like melancholy, magnifies trifles; but the magnifying of the one is like looking through a telescope at heavenly objects; that of the other, like enlarging monsters with a microscope.
The Correspondence of Leigh Hunt - vol. 1, Página 31 http://books.google.com.br/books?id=nDkmefUrJf0C&pg=PA31, de Thornton Leigh Hunt, Smith, Elder, and Co.. - publicado por Smith, Elder and Co., 1862

Variante: O objectivo mais alto do artista consiste em exprimir na fisionomia e nos movimentos do corpo as paixões da alma.

“A loucura de uma pessoa é a realidade de outra”
Site http://www.brainyquote.com/quotes/authors/t/tim_burton.html