Method

Observation

Overview

Observation in the natural sciences refers to the active acquisition of information from a primary source. It involves the act of noticing or perceiving phenomena and gathering data based on direct engagement with the subject of study.

In living organisms, observation typically occurs through the senses. In science, it often extends beyond unaided perception, involving the use of scientific instruments to detect, measure, and record data. This enables the observation of phenomena not accessible to human senses alone.

Observations in science are typically categorized as either qualitative or quantitative:

Qualitative observations describe characteristics that are not expressed numerically, such as color, texture, or behavior.

Quantitative observations involve numerical measurements, obtained through counting or using instruments to assign values to observed phenomena.

The term observation may refer both to the process of observing and to the information recorded as a result of that process.

Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).

In the original texts

Passages from public-domain books where Observation is discussed.

I. They rest upon the sound assumption that observation is an _active_ process. Observation is exploration, inquiry for the sake of discovering something previously hidden and unknown, this something being needed in order to reach some end, practical or theoretical. Observation is to be discriminated from recognition, or perception of what is familiar. The identification of something already understood is, indeed…
John Dewey, How We Think
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Friends and children give verbal expression to their disgust: chimpanzees are expressive, though not verbal. All these facts lead you to state: “The smell of assafœtida is unpleasant”. Although self-observation is involved, the result has the same kind of certainty, and the same kind of objective verification, as if it were one of the facts that form the empirical basis of physics.
Bertrand Russell, Philosophy
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On the other hand, a quality or relation of even a familiar object may previously have been passed over, and be just the fact that is helpful in dealing with the question. In this case direct observation is called for. The same principle applies to the use to be made of observation on one hand and of reading and "telling" on the other. Direct observation is naturally more vivid and vital. But it has its limitations…
John Dewey, Democracy and Education
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In order to see these remarks verified by the actual state of the sciences, we have only to think of the condition of natural history. In zoology, for example, there is an immense number of uniformities ascertained, some of coexistence, others of succession, to many of which, notwithstanding considerable variations of the attendant circumstances, we…
John Stuart Mill, A System of Logic
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I shall use it in a sense, in which we can certainly be said to observe nothing but ourselves, our own perceptions, thoughts and feelings, and what we directly perceive. And in the second place, it may be said that observations made by another person may give _me_ a reason for believing some generalisation.
G. E. Moore, Philosophical Studies
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Observation

Overview

In the original texts

Philosophers who discussed Observation

Related ideas

Place in the tradition