Human knowledge and human power meet in one; for where the cause is not known the effect cannot be produced. Nature to be commanded must be obeyed; and that which in contemplation is as the cause is in operation as the rule.
Conversation with a friend will only bear good fruit of knowledge when both think only of the matter under consideration and forget that they are friends.
The thief steals from himself. The swindler swindles himself. For the real price is knowledge and virtue, whereof wealth and credit are signs. These signs, like paper money, may be counterfeited or stolen, but that which they represent, namely, knowledge and virtue, cannot be counterfeited or stolen.
The essential form of knowledge... is nothing but a representation of truth: for the truth of being and the truth of knowing are one, differing no more than the direct beam and the beam reflected.
If the fresh facts come to our knowledge all fit themselves into the scheme, then our hypothesis may gradually become a solution. Sherlock Holmes speaking with Dr. Watson.