“In spite of the intellectual compression which has held humanity down for so many centuries, science has been able to progress and develop, thanks to the critical spirit of individuals refractory to official teaching and ready-made conceptions. It ought, then, to be put within the reach of all, to become accessible to all aptitudes, in order that this spirit of criticism which has saved it from obscurantism may contribute to hasten its full efflorescence.
“Knowledge is divided into so many diverse branches that it is impossible for the same individual to know them all in their entirety, the duration of a human life being far from sufficient for a man to acquire enough ideas to be able to investigate them in their minutest details.
“To study them,—that is, if he expects to be able to criticise them,—he is forced to have recourse to the labours of his predecessors and also of his contemporaries.
“It is from all human knowledge that the general synthesis must proceed. What we know to-day is only a means for acquiring the knowledge of to-morrow. And an individual obtains reliable knowledge only in accepting the help of all. The observations of the humblest persons are not always to be disdained. Let the savants also, then, cease to believe themselves a caste apart, let them understand once for all that knowledge does not demand special aptitudes, and that it must be accessible to all, in order that all, in developing themselves, may contribute thus to the general development.”
“What is true for individuals is true for nations. Just as an individual cannot live without the support of all, a people cannot exist without the co-operation of the other peoples. A nation which should shut itself up within its frontiers, ceasing all relations with the rest of the world, would not be slow to retrograde and perish. It is then absurd and criminal to foment, under colour of patriotism, hatreds nominally national, but which are in reality only pretexts for the governing classes to legitimise the scourge, militarism, of which they have need to assure their power.
“Every nation has need of the other nations. There is not a region which, for one product or another, is not the customer of another region. And it is no reason for you to hate your neighbours because they speak a different language, because a hundred years ago they invaded and ravaged regions which are indifferent to you to-day; and it is no reason for you to feel yourselves outraged by this ancient invasion because, once upon a time, the inhabitants of the invaded regions suffered under the yoke which now galls you.