Their incessant calculation of their own brains and other people's brains is a dangerous trade.

It is always perilous to the mind to reckon up the mind.

A flippant person has asked why we say, "As mad as a hatter." A more flippant person might answer that a hatter is mad because he has to measure the human head.
And if great reasoners are often maniacal, it is equally true that maniacs are commonly great reasoners.

When I was engaged in a controversy with the _Clarion_ on the matter of free will, that able writer Mr.R.B.Suthers said that free will was lunacy, because it meant causeless actions, and the actions of a lunatic would be causeless.

I do not dwell here upon the disastrous lapse in determinist logic.