During the last years of his abode in the island, he had killed or marked thus nearly five hundred.[1] [Footnote 1: Long after his departure from Juan Fernandez, the ship's crews, who came there for supplies, or the pirates who took refuge there, found goats whose ears had been slit by Selkirk's knife.] In the natural course of things, as his physical powers increased, his intelligence became enfeebled.
Necessity had at first aroused his industry, for all industry awakes at the voice of want; but his own had been due rather to his recollections than to his ingenuity.

He thought himself a creator, he was only an imitator.
Whatever may have been said by those who, in the pride of a deceitful philosophy, have wished to glorify the power of the solitary man--if the latter, supported by certain fortunate circumstances, can remain some time in a state hardly endurable, it is not by his own strength, but by means which society itself has furnished.

This is the incontestable truth, from which, in his pride, Selkirk had turned away.
Deprived of exercise and of aliment, his thoughts, no longer sustained by reading the Holy Book, were day by day lost in a chaos of dreams and reveries.
A prey to terrors which he could not explain, he feared darkness, he trembled at the slightest sound of the wind among the branches; if it blew violently, he thought the trees would be uprooted and crush him; if the sea roared, he trembled at the idea of the submersion of his entire island.
When he traversed the woods, especially if the heat was great, he often heard, distinctly, voices which called him or replied.

He caught entire phrases; others remained unfinished.

These phrases, connected neither with his thoughts nor his situation, were strange to him.
Sometimes he even recognized the voice.
Now it was that of Catherine, scolding her servants; now that of Stradling, of Dampier, or one of his college tutors.