Definition of "observation"

But Miss Thorn relieved the situation by laughing aloud, […] . We began to tell her about Mohair and the cotillon, and of our point of observation from the Florentine galleried porch, and she insisted she would join us there.

1897 December (indicated as 1898), Winston Churchill, chapter V, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd.

The physics of elementary particles in the 20th century was distinguished by the observation of particles whose existence had been predicted by theorists sometimes decades earlier.

2012 March-April, Jeremy Bernstein, “A Palette of Particles”, in American Scientist, volume 100, number 2, page 146

That's a foolish observation.

c. 1591–1592 (date written), William Shakespeare, “The Third Part of Henry the Sixt, […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act II, scene vi]

To observations which ourselves we make / We grow more partial for the observer's sake.

1734, Alexander Pope, Of the Knowledge and Characters of Men

This hypothesis goes by many names, including group resistence, the threshold effect, and the gender paradox. Because the hypothesis holds such wide appeal, it is worth revisiting the logic behind it. The hypothesis is built on the factual observation that fewer females than males act antisocially.

2001 September 27, Terrie E. Moffitt, Avshalom Caspi, Michael Rutter, Phil A. Silva, Sex Differences in Antisocial Behaviour: Conduct Disorder, Delinquency, and Violence in the Dunedin Longitudinal Study‎, Cambridge University Press, page 151

We are to procure dispensation or leave to omit the observation of it in such circumstances.

1651, Jer[emy] Taylor, The Rule and Exercises of Holy Living. […], 2nd edition, London: […] Francis Ashe […]