Experiment is another material ground of induction. In case of experiment some phenomena of nature are studied under pre-arranged conditions.

Experiment can be explained as artificial reproduction of events under controlled conditions. Bacon considers that in experiment we interrogate nature.

In experiment there is a definite purpose i.e. to arrive at a conclusion on the basis of the findings under conditions selected and prearranged by the experimenter.

Experiments are widely used by the scientists and considered to be the part and parcel of the subject matter of sciences. Experiments become the basis of establishing scientific truths.

ADVERTISEMENTS:

Experiments are mostly conducted in the laboratories by scientific instruments. Bain considers that experiment is a method of ‘making of fact’ in the sense of establishing the generalized truth about the fact. A fact is directly experienced in case of an experiment.

It is quite important to note that even through experiment is considered as a separate material ground of induction (as compared to observation) no experiment can be conducted without observations.

That is experiments are also observed and the former cannot do away with the latter. But while experiment requires active involvement of the experimenter to reproduce some event observation studies phenomena only when they occur in nature. In this sense some logicians consider that observation is passive whereas experiment is active. 1

We find water as a part of the natural phenomena. Scientists have experimented with water and have found it to be the combination of hydrogen and oxygen at a particular ratio. This view or the conclusion of the scientists has been accepted as a general truth on the ground of experiments.

ADVERTISEMENTS:

Any one can verify this truth under the agreement of certain conditions. The verification can be done for any number of times also. Thus the experiments help us in arriving at an acceptable truth and the experiments are always within our control.

Natural experiments:

Sometimes nature creates a special circumstance for our observation of some event, it is called natural experiment. Where nature makes the arrangements for the production of a definite effect, Jevon calls it natural experiment. For example, before the invention of rockets or the satellites it was not possible to know the shape of the earth.

But special circumstances of nature like eclipses, have helped to know the shape of the earth through its shadow.

ADVERTISEMENTS:

This knowledge regarding the shape of the earth could be possible through special circumstances of nature i.e. eclipses. Such type of cases is considered to be natural experiments by Jevon.

Strictly considering such types of cases need not be named as experiments. Because adequate justification cannot be given to consider those to be experiments. Experiments are arranged ones. Nature cannot be treated as an arranger. So it is not proper to consider them as experiments.