I found the first hint that occurs to indicate the lines of his later life, in a letter to his father, written in his last week at Cambridge.

In the Classical Tripos Arthur contrived to secure a second; in the translations, notably Greek, we heard he did as well as anybody; but history and other detailed subjects dragged him down: it was an extraordinarily unequal performance.
His father, being ambitious for his sons, and knowing to a certain extent Arthur's ability, was altogether a good deal disappointed.

He had accepted Arthur's failure to get a scholarship or exhibition, not with equanimity, but with a resolute silence, knowing that strict scholarship was not his son's strong point, but still hoping that he would at least do well enough in his Tripos to give him a possibility of a Fellowship.
Arthur would himself have been happier with a Fellowship than with any other position, but the possibility did not stimulate him to work with that aim in view.

He wrote: "Existence generally is so extremely problematical, that I can not consent to throw away three birds in the hand for one which I do not believe to be in the bush--my present life for a doubtful future provision.

I think I am ambitious after the event.