“Theories are like a stairway; by climbing, science widens its horizon more and more, because theories embody and necessarily include proportionately more facts as they advance.”

Priestley said that each discovery we make shows us many others that should be made.

With the aid of these active experimental sciences man becomes an inventor of phenomena, a real foreman of creation; and under this head we cannot set limits to the power that he may gain over nature through future progress of the experimental sciences.

The minds that rise and become really great are never self-satisfied, but still continue to strive.

But while I accept specialization in the practice, I reject it utterly in the theory of science.

Science does not permit exceptions.

All the vital mechanisms, varied as they are, have only one object, that of preserving constant the conditions of life in the internal environment.

A fact in itself is nothing. It is valuable only for the idea attached to it, or for the proof which it furnishes.

Put off your imagination, as you put off your overcoat, when you enter the laboratory. Put it on again, as you put on your overcoat, when you leave.

In the philosophic sense, observation shows and experiment teaches.

In teaching man, experimental science results in lessening his pride more and more by proving to him every day that primary causes, like the objective reality of things, will be hidden from him forever and that he can only know relations.

Hatred is the most clear- sighted, next to genius.

Feeling alone guides the mind.

We must alter theory to adapt it to nature, but not nature to adapt it to theory.‎

Science rejects the indeterminate.

Art is ‘I’; science is ‘we’.

Those who have an excessive faith in their theories or in their ideas are not only poorly disposed to make discoveries, but they also make very poor observations.

Ignorance was just as dynamic as knowledge, and it grew in the same proportion.

The pleasures of love are always in proportion to our fears.

I like to eat in proportion, eat healthy, home-cooked food with lots of salad.

Your success is directly proportional to the quality of the relationships in your life.

Your life unfolds in proportion to your courage.

The fixity of a habit is generally in direct proportion to its absurdity.

Most people experience both tragedy and joy in varying proportions. Any philosophy which leaves out either cannot be considered to be comprehensive.

Justice has always evoked ideas of Equality, of proportion of compensation. In short, Justice is another name of Liberty, Equality and Fraternity.