If two or more instances of the phenomenon under investigation have only one circumstance in common, the circumstance in which alone all the instances agree is the cause (or effect) of the given phenomenon.

It is not the feeling sure of a doctrine (be it what it may) which I call an assumption of infallibility. It is the undertaking to decide that question for others, without allowing them to hear what can be said on the contrary side. And I denounce and reprobate this pretension not the less, if put forth on the side of my most solemn convictions.

We have a right, also, in various ways, to act upon our unfavorable opinion of anyone, not to the oppression of his individuality, but in the exercise of ours.

All attempts by the State to bias the conclusions of its citizens on disputed subjects, are evil.

Any participation, even in the smallest public function, is useful.

A cultivated mind is one to which the fountains of knowledge have been opened, and which has been taught, in any tolerable degree, to exercise its faculties.

Over one's mind and over one's body the individual is sovereign.