14. Decay of perception in old age.
But yet I cannot but think there is some small dull perception, whereby they
are distinguished from perfect insensibility. And that this may be so, we have plain instances, even in mankind
itself. Take one in whom decrepit old age has blotted out the memory of his past knowledge, and clearly wiped
out the ideas his mind was formerly stored with, and has, by destroying his sight, hearing, and smell quite, and his
taste to a great degree, stopped up almost all the passages for new ones to enter; or if there be some of the inlets
yet half open, the impressions made are scarcely perceived, or not at all retained. How far such an one
(notwithstanding all that is boasted of innate principles) is in his knowledge and intellectual faculties above the
condition of a cockle or an oyster, I leave to be considered. And if a man had passed sixty years in such a state, as
it is possible he might, as well as three days, I wonder what difference there would be, in any intellectual
perfections, between him and the lowest degree of animals.
