enough to make it worth while trying whether as a
matter of fact it has. It is said that a general resemblance of the
hills near Ballarat in Australia to the Californian hills where gold
had been found suggested the idea of digging for gold at Ballarat.
This was a lucky issue to an argument from analogy, but doubtless many
have dug for gold on similar general resemblances without finding that
the resemblance extended to that particular. Similarly, many of
the extensions of the Pharmacopeia have proceeded upon general
resemblances, the fact that one drug resembles another in certain
properties being a sufficient reason for trying whether the
resemblance goes further. The lucky guesses of what is known as
natural sagacity are often analogical. A man of wide experience in any
subject-matter such as the weather, or the conduct of men in war, in
business, or in politics, may conclude to the case in hand from some
previous case that bears a general resemblance to it, and very often
his conclusions may be perfectly sound though he has not made a
numerical estimate of the data.

The chief source of fallacy in analogical argument is ignoring the
number of points of difference. It often happens that an amount of
resemblance only sufficient for a rhetorical simile is made to do duty
as a solid argument. Thus the resemblance between a living body
and the body politic is sometimes used to support inferences from
successful therapeutic treatment to State policy. The advocates of
annual Parliaments in the time of the Commonwealth based their case on
the serpent's habit of annually casting its skin.

Wisest of beasts the serpent see,
Just emblem of eternity,
And of a State's duration;
Each year an annual skin he takes,
And with fresh life and vigour wakes
At every renovation.

Britain! that serpent imitate.
Thy Commons House, that skin of State,
By annual choice restore;
So choosing thou shall live secure,
And freedom to thy sons inure,
Till Time shall be no more.

Carlyle's saying that a ship could never be taken round Cape Horn if
the crew were consulted every time the captain proposed to alter
the course, if taken seriously as an analogical argument against
Representative Government, is open to the objection that the
differences between a ship and a State are too great for any argument
from one to the other to be of value. It was such fallacious analogies
as these that Heine had in view in h