of the object. When, for instance, a
man remembers his absent son, he does not directly perceive him, but
merely wishes so to perceive him. As thus the distinction between the
two states is evident to every one, it is impossible to formulate the
inference that waking consciousness is false because it is mere
consciousness, such as dreaming consciousness; for we certainly cannot
allow would-be philosophers to deny the truth of what is directly
evident to themselves. Just because they feel the absurdity of denying
what is evident to themselves, and are consequently unable to
demonstrate the baselessness of the ideas of the waking state from those
ideas themselves, they attempt to demonstrate it from their having
certain attributes in common with the ideas of the dreaming state. But
if some attribute cannot belong to a thing on account of the latter's
own nature, it cannot belong to it on account of the thing having
certain attributes in common with some other thing. Fire, which is felt
to be hot, cannot be demonstrated to be cold, on the ground of its
having attributes in common with water. And the difference of nature
between the waking and the sleeping state we have already shown.

30. The existence (of mental impressions) is not possible on the
Bauddha view, on account of the absence of perception (of external
things).

We now proceed to that theory of yours, according to which the variety
of ideas can be explained from the variety of mental impressions,
without any reference to external things, and remark that on your
doctrine the existence of mental impressions is impossible, as you do
not admit the perception of external things. For the variety of mental
impressions is caused altogether by the variety of the things perceived.
How, indeed, could various impressions originate if no external things
were perceived? The hypothesis of a beginningless series of mental
impressions would lead only to a baseless regressus ad infinitum,
sublative of the entire phenomenal world, and would in no way establish
your position.--The same argument, i.e. the one founded on the
impossibility of mental impressions which are not caused by external
things, refutes also the positive and negative judgments, on the ground
of which the denier of an external world above attempted to show that
ideas are caused by mental impressions, not by external things. We
rather have on our side a positive and a negative judgment whereby to
establish our