Before turning to those moral and mental aspects of the matter which present the greatest difficulties, let the inquirer begin by mastering more elementary problems.
How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?
It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.
We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth.