Lucifer's Hammer

by Larry Niven

The Earth is just too small and fragile a basket for the human race to keep all its eggs in.

The value of a thing is what that thing will bring.

In any ethical situation, the thing you want least to do is probably the right action.

Everything that is called duty, the prerequisite for all genuine law and the substance of every noble custom, can be traced back to honor. If one has to think about it, one is already without honor,

The importance of information is directly proportional to its improbability. - Fundamental theorem of information theory

To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection.