“The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.”

Ich vermeinte, man verlange physische Determinationen und nicht abstracte integrationes. Es fängt sich ein verderblicher goût an einzuschleichen, durch welchen die wahren Wissenschaften viel mehr leiden, als sie avancirt werden, und wäre es oft besser für die realem physicam, wenn keine Mathematik auf der Welt wäre.
Letter to Leonhard Euler, 26 January 1750, published in [Correspondance mathématique et physique de quelques célèbres géomètres du XVIIIème siècle, P. H. Fuss, Saint Petersburg, 1843, 650]

Les progrès scientifiques ont amené les philosophes à détourner leur attention de l’explication des phénomènes physiques, abandonnée désormais à la science, pour la diriger vers le problème de l’être lui-même.
La voile d'Isis: Essai sur l'histoire de l'idée de Nature (2004)

Source: 1950s, The development of operations research as a science, 1956, p. 265, the lead paragraph ; Cited in: Joe Kelly (1969) Organizational behaviour. p. 26.

Source: Extremely Loud and Incredibly Close

Campaign speech http://www.whitehouse.gov/the-press-office/2012/08/08/remarks-president-campaign-event, Grand Junction High School, Colorado, , quoted in
Furthermore compare what Obama said in 2009
2012
Context: Now, when we came together, we knew restoring that bargain — that deal, that compact — was not going to be easy. We knew it would take more than one year or one term or maybe even one President, because we had seen what had happened in the previous decade. Jobs had moved overseas. Folks were working harder and harder, but their wages or incomes, they were staying flat, sometimes even going down. The cost of everything from health care to college was going up. And then, it all culminated in the worst economic crisis since the Great Depression — a crisis that robbed too many of our friends and our neighbors of jobs, the value of their homes, their savings. And all that pushed the American Dream even further out of reach for too many working people.

1894, dedication of Ryerson Physical Laboratory, quoted in Annual Register 1896, p. 159 https://books.google.com/books?id=HysXAAAAYAAJ&pg=PA159.
Variants of this quote have been misattributed to Lord Kelvin since the 1980s, though there is no evidence that he said anything of the sort. The identity of the unnamed "eminent physicist" is unknown.

As quoted by Morris Kline, Mathematics and the Physical World (1959) Ch. 25: From Calculus to Cosmic Planning, pp. 441–42.

"The Magic of Science" in Imperial Oil Review (Spring, 1994) http://sites.utoronto.ca/jpolanyi/public_affairs/public_affairs4f.html.
Context: It is not the laws of physics that make science possible but the unprovable proposition that there exists a grand design underlying the physical world. And not just any old "grand design" but one that is accessible to the limited senses and modest reasoning powers of the species to which we belong. Scientists subscribe with such conviction to this article of faith that they are willing to commit a lifetime to the pursuit of scientific discovery. It is hardly surprising that an activity so magical is also undefinable. Science is what scientists do. And what they do is look around themselves for messages written in the sky, the earth, the oceans and all living things – messages that tell of the unity of creation. These messages have been there – unseen, though at times written in letters miles high – since the dawn of history. But we have just passed through an epoch in which, quite suddenly, scientists seem to have learnt speed reading. Discoveries have been coming at an unprecedented pace. In the wake of such a period it is common to consider that we may be approaching the point where all that is readable in nature will have been read. We should be skeptical of such claims. Success in reading some messages brings with it a temporary blindness to others. We forget that between the words written in black in nature's book there are likely to be messages of equal importance written in white. It is a truism that success in science comes to the individuals who ask the right questions.

Source: The systems view of the world (1996), p. 8 as cited in: Martha C. Beck (2013) "Contemporary Systems Sciences, Implications for the Nature and Value of Religion, the Five Principles of Pancasila, and the Five Pillars of Islam," Dialogue and Universalism-E Volume 4, Number 1/2013. p. 3 ( online http://www.emporia.edu/~cbrown/dnue/documents/vol04.no01.2013/Vol04.01.Beck.pdf).