"self-reliance" is an example of

the word that best matches the meaning of the expression "went to the big ocean" is died.

the goldfish died, which is why the father looks at the children mournfully. the "big ocean" is the father's way of saying fish heaven. he could have just said that the goldfish died, but this way, the children imagine the fish in a bigger, better place instead of just picturing a dead fish.

explanation:

in the door-way, with his head in the room and with a lantern in hand with the most slight ray of light shining from it; so small and opening it so slowly to not disturb the old mans sleep.

i have watched the play of this story last friday.