happiness or enjoyment! What is there left of them now? Only the ghost
of a remembrance! And it is the same with everything that really falls
to our lot. So that the _form of time_ itself, and how much is reckoned
on it, is a definite way of proving to us the vanity of all earthly
enjoyment.

Our existence, as well as that of all animals, is not one that lasts, it
is only temporary, merely an _existentia fluxa_, which may be compared
to a water-mill in that it is constantly changing.

It is true that the _form_ of the body lasts for a time, but only on
condition that the matter is constantly changing, that the old matter is
thrown off and new added. And it is the chief work of all living
creatures to secure a constant supply of suitable matter. At the same
time, they are conscious that their existence is so fashioned as to last
only for a certain time, as has been said. This is why they attempt,
when they are taking leave of life, to hand it over to some one else who
will take their place. This attempt takes the form of the sexual
instinct in self-consciousness, and in the consciousness of other things
presents itself objectively--that is, in the form of genital instinct.
This instinct may be compared to the threading of a string of pearls;
one individual succeeding another as rapidly as the pearls on the
thread. If we, in imagination, hasten on this succession, we shall see
that the matter is constantly changing in the whole row just as it is
changing in each pearl, while it retains the same form: we will then
realise that we have only a quasi-existence. That it is only Ideas which
exist, and the shadow-like nature of the thing corresponding to them, is
the basis of Plato's teachings.

That we are nothing but _phenomena_ as opposed to the thing-in-itself is