Directions: The short passage below is followed by a question based on its content. Answer the question on the basis of what is stated or implied in the passage.
Whatever is, is in some sense the seed of what is to emerge from it… To be in process of change is not an evil, any more than to be the product of change is a good… Time is a river, the resistless flow of all created things. One thing no sooner comes in sight than it is hurried past and another is borne along, only to be swept away in its turn…What follows is ever closely linked to what precedes; it is not a procession of isolated events, merely obeying the laws of sequence, but a rational continuity. Moreover, just as things already in existence are all harmoniously coordinated, things in the act of coming into existence exhibit the same marvel of concatenation, rather than simply the bare fact of succession.
What is the theme of the passage?