I said in my heart,
“Concerning the condition of the sons of men, God tests them, that they may see that they themselves are like animals.”
For what happens to the sons of men also happens to animals; one thing befalls them: as one dies, so dies the other. Surely, they all have one breath; man has no advantage over animals, for all is vanity. All go to one place: all are from the dust, and all return to dust. Who knows the spirit of the sons of men, which goes upward, and the spirit of the animal, which goes down to the earth?
(Ecclesiastes 3:18-21, nkjv)
Solomon says God intends to make us know that we are just like the animals,
that we all have the same breath, that we all are made of dust and return to dust.
he writes this as though yes, the creature has a spirit - no different than man, who is himself a creature
he also writes this as tho the spirit of the creature continues existing after the body returns to dust:
the body is from dust, and returns to dust. the spirit tho: what happens to it? it isn't made of dust; does it go to dust?
verse 21 is a question - footnotes from my nkjv say:
Ecclesiastes 3:21 LXX, Syr., Tg., Vg. Who knows whether the spirit . . . goes upward, and whether . . . goes downward to the earth?
which jives with the following verse:
So I perceived that nothing is better than that a man should rejoice in his own works, for that is his lot. For who can bring him to see what will happen after him?
(Ecclesiastes 3:22)
who knows what will happen after our bodies go back to dust?
does the spirit of the creature go up or go down? - men are 'living creatures' too
later towards the end of the writing, Solomon answers the question, where does the spirit go when it's separated from the body?
Remember your Creator before the silver cord is loosed,
Or the golden bowl is broken,
Or the pitcher shattered at the fountain,
Or the wheel broken at the well.
Then the dust will return to the earth as it was,
And the spirit will return to God who gave it.
(Ecclesiastes 12:6-7)
the question from 3:21 here has its conclusion:
the body is dust and goes to dust
the spirit is heavenly and returns to God who gave it
which is,
the spirit of life is a gift, and it doesn't die like the body of dust does.
remembering chapter 3 when we get to chapter 12, Solomon is saying this about man and other creatures alike