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BOX 3-1

Pasteur’s Quadrant

The writers of this report, like many others, faced a semantic question in the discussions of different kinds of research. Basic research, presumably pursued for the sake of fundamental understanding but without thought of use, generally is distinguished from applied research, which is pursued to convert basic understanding into practical use. This view, called the “linear model” is shown here:

But that classification quickly breaks down in the real world because “basic” discoveries often emerge from “applied” or even “developmental” activities. In his 1997 book, Pasteur’s Quadrant,a Donald Stokes responded to that complexity with a more nuanced classification that describes research according to intention. He distinguishes four types:

  • Pure basic research, performed with the goal of fundamental understanding (such as Bohr’s work on atomic structure).

  • Use-inspired basic research, to pursue fundamental understanding but motivated by a question of use (such as Pasteur’s work on the biologic bases of fermentation and disease).

  • Pure applied research, motivated by use but not seeking fundamental understanding (such as that leading to Edison’s inventions).

  • Applied research that is not motivated by a practical goal (such as plant taxonomy).

In Stokes’s argument, research is better depicted as a box than as a line:

In contrast to the basic–applied dichotomy, Stokes’s taxonomy explicitly recognizes research that is simultaneously inspired by a use but that also seeks fundamental knowledge, which he calls “Pasteur’s Quadrant.”


aD. Stokes. Pasteur’s Quadrant. Washington, DC: Brookings Institution Press, 1997.

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