Hobbes and Locke

Thomas Hobbes (1588-1679) argued that the difference between a living thing and a dead thing is not that living things have a soul but simply the physical fact that living things have bodily functions and/or voluntary movements, and dead things do not.  In human beings all voluntary movement is caused by desire or aversion (the opposite of desire) and, since these things cause movement, these too are kinds of movement.  So psychology can be explained in purely physical, material, mechanistic terms without any need to refer to souls or God.

What about ethics?  Hobbes explains good and evil physically too.  "Good", he says, is just what we call things we like, and "evil" is what we call things to which we are averse. 

And politics?  In a state of nature, with no government at all, competition for limited resources, fear of others, and desire for glory would make war (at least a kind of cold war) between individuals inevitable.  Life would be solitary, poor, nasty, brutish, and short.  Our only hope is to give up our rights to one person or body (a government) to rule over us all and protect us from outside enemies and internal criminals.  Disobedience or rebellion would be suicidal, plunging us back into anarchy, and so wrong.

John Locke (1632-1704) disagreed.  By nature, he said, all beings of the same species are, and should be, equal.  All people have a natural right to life, health, liberty, and possessions.  Any human law that contradicts the natural law is invalid, and we have no moral obligation to obey it.