Positive selection may refer to:
- Positive selection as an event during thymocyte maturation
- Directional selection, a particular mode or mechanism of natural selection.
Famous quotes containing the words positive and/or selection:
“As for the terms good and bad, they indicate no positive quality in things regarded in themselves, but are merely modes of thinking, or notions which we form from the comparison of things with one another. Thus one and the same thing can be at the same time good, bad, and indifferent. For instance music is good for him that is melancholy, bad for him who mourns; for him who is deaf, it is neither good nor bad.”
—Baruch (Benedict)
“The books for young people say a great deal about the selection of Friends; it is because they really have nothing to say about Friends. They mean associates and confidants merely.”
—Henry David Thoreau (1817–1862)