We will be victorious if we have not forgotten how to learn.

The more that social democracy develops, grows, and becomes stronger, the more the enlightened masses of workers will take their own destinies, the leadership of their movement, and the determination of its direction into their own hands.

The high stage of world-industrial development in capitalistic production finds expression in the extraordinary technical development and destructiveness of the instruments of war.

Freedom is always the freedom of dissenters.

Capitalism, as a result of its own inner contradictions, moves toward a point when it will be unbalanced, when it will simply become impossible.

There is no democracy without socialism, and no socialism without democracy.

On the one hand, we have the mass; on the other, its historic goal, located outside of existing society. On one hand, we have the day-to-day struggle; on the other, the social revolution. It follows that this movement can best advance by tacking betwixt and between the two dangers by which it is constantly being threatened. One is the loss of its mass character; the other, the abandonment of its goal. One is the danger of sinking back to the condition of a sect; the other, the danger of becoming a movement of bourgeois social reform.