Professor Nathan EnsmengerHistory & Sociology of Science

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Professor Nathan EnsmengerHistory & Sociology of Science

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Professor Nathan EnsmengerHistory & Sociology of Science

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Thomas S. Kuhn, 1922-1996B.S. in Physics, Harvard University, 1943

MA, PhD in Physics, Harvard University, 1946-1949

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Scientific

Science

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Scientific

Science

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

ScientificScience

Science

• (noun) [sci·enc·es]

1 : a department of systematized knowledge as an object of study

2 : knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method

Science

• (noun) [sci·enc·es]

1 : a department of systematized knowledge as an object of study

2 : knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method

Science

• (noun) [sci·enc·es]

1 : a department of systematized knowledge as an object of study

2 : knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method

“If I have seen further, it is by standing on the shoulders of giants.”

Sir Isaac Newton, 1643-1727

Science as cumulative progress

Science as cumulative progress

Science as cumulative progress

Science as cumulative progress

Science as cumulative progress

Science as cumulative progress

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Revolutions

Revolution

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

Revolutions

Revolution

The Structure of Scientific Revolutions

The Social Context of Scientific Discovery

RevolutionsRevolution

Revolution

• (noun) [rev·o·lu·tions]

1 : the action by a celestial body of going round in an orbit or elliptical course;

2 : a) sudden, radical, or complete change b) : a fundamental change in political organization; c) : activity or movement designed to effect fundamental changes in the socioeconomic situation d) : a fundamental change in the way of thinking about or visualizing something : a change of paradigm <the Copernican revolution>

Revolution

• (noun) [rev·o·lu·tions]

1 : the action by a celestial body of going round in an orbit or elliptical course;

2 : a) sudden, radical, or complete change b) : a fundamental change in political organization; c) : activity or movement designed to effect fundamental changes in the socioeconomic situation d) : a fundamental change in the way of thinking about or visualizing something : a change of paradigm <the Copernican revolution>

Revolution

• (noun) [rev·o·lu·tions]

1 : the action by a celestial body of going round in an orbit or elliptical course;

2 : a) sudden, radical, or complete change b) : a fundamental change in political organization; c) : activity or movement designed to effect fundamental changes in the socioeconomic situation d) : a fundamental change in the way of thinking about or visualizing something : a change of paradigm <the Copernican revolution>

Revolution

• (noun) [rev·o·lu·tions]

1 : the action by a celestial body of going round in an orbit or elliptical course;

2 : a) sudden, radical, or complete change b) : a fundamental change in political organization; c) : activity or movement designed to effect fundamental changes in the socioeconomic situation d) : a fundamental change in the way of thinking about or visualizing something : a change of paradigm <the Copernican revolution>

Normal Science Crisis

Anomalies

Revolution

Kuhnian Paradigm Shift

Normal Science is what most scientists mostly do.

Paradigms:Accepted examples of actual scientific practice -- examples which include law, theory, application, and instrumentation together -- that provide models from which spring particular coherent traditions of scientific research.

The Structure of Scientific Revolutions, p. 11.

The Ptolemaic Universe

Revolution

• (noun) [rev·o·lu·tions]

1 : the action by a celestial body of going round in an orbit or elliptical course;

2 : a) sudden, radical, or complete change b) : a fundamental change in political organization; c) : activity or movement designed to effect fundamental changes in the socioeconomic situation d) : a fundamental change in the way of thinking about or visualizing something : a change of paradigm <the Copernican revolution>

Copernicus: Conversation with God Jan Matejko, 1872

Nicholas Copernicus, On the Revolutions of the Celestial Spheres (1543)

The Ptolemaic Universe

Normal Science Does Not Aim at Novelty

Normal Science Does Not Aim at Novelty

"Normal science does not aim at novelties of fact or theory and, when successful, finds none."

The Structure of Scientific Revolutions (52)

Mars in Retrograde Motion

There can be no paradigm change without

crisis.

Discoveries are rare because expectations

cloud our vision.

The decision to reject one paradigm is always a

decision to accept another.

The decision to reject one paradigm is always a

decision to accept another.

“To reject one paradigm without substituting another is to reject science itself.”

The Structure of Scientific Revolutions, p. 79.

Science is non-cumulative because terms change their

meanings.

Science is non-cumulative because terms change their

meanings.

Sometimes F≠MA ...

“Though the world does not change with a change of paradigm, the scientist afterwards works in a different world.”

The Structure of Scientific Revolutions, p. 121.

“Though the world does not change with a change of paradigm, the scientist afterwards works in a different world.”

The Structure of Scientific Revolutions, p. 121.

Paradigms are Incommensurable.

“Though the world does not change with a change of paradigm, the scientist afterwards works in a different world.”

The Structure of Scientific Revolutions , p. 121.

Normal Science Crisis

Anomalies

Revolution

Kuhnian Paradigm Shift

Is Science Arbitrary?

Cloud Chamber Experiment, c. 2005