To believe with certainty we must begin with doubting.

If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty.

To believe with certainty we must begin with doubting.

Long ailments wear out pain, and long hopes, joy.

Have the courage to face a difficulty lest it kick you harder than you bargain for.

Science when well digested is nothing but good sense and reason.