because nature has given healing properties to all
plants. But 'logical' democrats still argue in America that, because all
men are equal, political offices ought to go by rotation, and 'logical'
collectivists sometimes argue from the 'principle' that the State should
own all the means of production to the conclusion that all railway
managers should be elected by universal suffrage.

In natural science, again, the conception of the plurality and
interaction of causes has become part of our habitual mental furniture;
but in politics both the book-learned student and the man in the street
may be heard to talk as if each result had only one cause. If the
question, for instance, of the Anglo-Japanese alliance is raised, any
two politicians, whether they are tramps on the outskirts of a Hyde Park
crowd or Heads of Colleges writing to the _Times_, are not unlikely to
argue, one, that all nations are suspicious, and that therefore the
alliance must certainly fail, and the other that all nations are guided
by their interests, and that therefore the alliance must certainly
succeed. The Landlord of the 'Rainbow' in _Silas Marner_ had listened to
many thousands of political discussions before he adopted his formula,
'The truth lies atween you: you're both right and both wrong, as I
allays say.'

In Economics the danger of treating abstract and uniform words as if
they were equivalent to abstract and uniform things has now been
recognised for the last half century. When this recognition began, it
was objected by the followers of the 'classical' Political Economy that
abstraction was a necessary condition of thought, and that all dangers
arising from it would be avoided if we saw clearly what it was that we
were doing. Bagehot, who stood at the meeting-point of the old Economics
and the new, wrote about 1876:--

'Political Economy ... is an abstract science, just as statics and
dynamics are deductive sciences. And in consequence, it deals with an
unreal and imaginary subject, ... not with the entire real man as we
know him in fact, but with a simpler imaginary man....'[41]

[41] _Economic Studies_ (Longmans, 1895), p. 97.

He goes on to urge that the real and complex man can be depicted by
printing on our minds a succession of different imaginary simple men.
'The maxim of science,' he says, 'is that of common-sense--simple cases
first; begin with seeing how the main force acts when there is as little
as possible to impede it,