The principles of ethics come from our own nature as social, reasoning beings.

Since ancient times, philosophers have maintained that to strive too hard for one's own happiness is self-defeating.

The only justifiable stopping place for the expansion of altruism is the point at which all whose welfare can be affected by our actions are included within the circle of altruism. This means that all beings with the capacity to feel pleasure or pain should be included; we can improve their welfare by increasing their pleasures and diminishing their pains.

There can be no brotherhood when some nations indulge in previously unheard of luxuries, while others struggle to stave off famine.

Beginning to reason is like stepping onto an escalator that leads upward and out of sight. Once we take the first step, the distance to be traveled is independent of our will and we cannot know in advance where we shall end.

The capacity to reason is a special sort of capacity because it can lead us to places that we did not expect to go.

Everyday we act in ways that reflect our ethical judgements.

Herbert Spencer is little read now. Philosophers do not regard him as a major thinker.

The core of ethics runs deep in our species and is common to human beings everywhere. It survives the most appalling hardships and the most ruthless attempts to deprive human beings of their humanity. Nevertheless, some people resist the idea that his core has a biological basis which we have inherited from our pre-human ancestors.

If evolution is a struggle for survival, why hasn't it ruthlessly eliminated altruists, who seem to increase another's prospects of survival at the cost of their own?