“Some circumstantial evidence is very strong, as when you find a trout in the milk.”
November 11, 1854
Referring to an 1849 dairyman's strike, during which there was suspicion of milk being watered down
Journals (1838-1859)
Variant: Some circumstantial evidence is very strong, as when you find a trout in the milk.
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Henry David Thoreau 385
1817-1862 American poet, essayist, naturalist, and abolitio… 1817–1862Related quotes

“Circumstantial evidence only raises a probability.”
Reg. v. Rowton (1865), 13 W. R. 437.

“Poems present their testimony as circumstantial evidences, not as closing argument.”
A Poets View (1984)
Context: Acknowledgement, and celebration, of mystery probably constitutes the most consistent theme of my poetry from its very beginnings. Because it is a matter of which I am conscious, it is possible, however imprecisely, to call it an intellectual position; but it is one which emphasizes the incapacity of reason alone (much though I delight in elegant logic) to comprehend experience, and considers Imagination the chief of human faculties. It must therefore be by the exercise of that faculty that one moves toward faith, and possibly by its failure that one rejects it as delusion. Poems present their testimony as circumstantial evidences, not as closing argument. Where Wallace Stevens says, "God and the imagination are one," I would say that the imagination, which synergizes intellect, emotion and instinct, is the perceptive organ through which it is possible, though not inevitable, to experience God.
"Got Milk? Might Not Be Doing You Much Good", in The New York Times (17 November 2014) http://www.nytimes.com/2014/11/18/upshot/got-milk-might-not-be-doing-you-much-good.html?_r=0

Part I, 4
The Kingfishers (1950)
Context: We can be precise. The factors are
in the animal and / or the machine the factors are
communication and / or control, both involve
the message. And what is the message? The message is
a discrete or continuous sequence of measurable events distributed in time is the birth of the air, is
the birth of water, is
a state between
the origin and
the end, between
birth and the beginning of
another fetid nest is change, presents
no more than itself And the too strong grasping of it,
when it is pressed together and condensed,
loses it This very thing you are

Early in 1976, speaking to Margaret Trudeau, according to page 317 of Just Watch Me: The Life of Pierre Elliott Trudeau, 1968-2000 https://books.google.ca/books?id=ACC_G_kiR4cC&pg=PA317&lpg=PA317 by John English.

“Wherever the trout are, it's beautiful.”