Even in respect to those crimes which seem perfectly beyond human foresight, such as murders committed in general at the close of quarrels, arising without a motive, and under other circumstances to all appearance the most fortuitous or accidental; nevertheless, experience proves that murders are committed annually, not only pretty nearly to the same extent, but even that the instruments employed are in the same proportions. Now, if this occurs in the case of crimes whose origin seems to be purely accidental, what shall we say of those admitted to be the result of reflection.

Introductory - A Treatise on Man and the Development of His Faculties (1842)