for it tended to confirm a sad suspicion that Moxon's devotion to
study and work in his machine-shop had not been good for him. I
knew, for one thing, that he suffered from insomnia, and that is no
light affliction. Had it affected his mind? His reply to my
question seemed to me then evidence that it had; perhaps I should
think differently about it now. I was younger then, and among the
blessings that are not denied to youth is ignorance. Incited by that
great stimulant to controversy, I said:

"And what, pray, does it think with--in the absence of a brain?"

The reply, coming with less than his customary delay, took his
favorite form of counter-interrogation:

"With what does a plant think--in the absence of a brain?"

"Ah, plants also belong to the philosopher class! I should be
pleased to know some of their conclusions; you may omit the
premises."

"Perhaps," he replied, apparently unaffected by my foolish irony,
"you may be able to infer their convictions from their acts. I will
spare you the familiar examples of the sensitive mimosa, the several
insectivorous flowers and those whose stamens bend down and shake
their pollen upon the entering bee in order that he may fertilize
their distant mates. But observe this. In an open spot in my garden
I planted a climbing vine. When it was barely above the surface I
set a stake into the soil a yard away. The vine at once made for it,
but as it was about to reach it after several days I removed it a few
feet. The vine at once altered its course, making an acute angle,