It is thus with almost all questions of political economy.
If you say, for instance: There is a machine which has turned out of employment thirty workmen;
Or again: There is a spendthrift who encourages every kind of industry;
Or: The conquest of Algiers has doubled the commerce of Marseilles;
Or, once more: The public taxes support one hundred thousand families;
You are understood at once; your propositions are clear, simple, and true in themselves. If you deduce from them the principle that
Machines are an evil;
That sumptuous extravagance, conquest, and heavy imposts are blessings;
Your theory will have the more success, because you will be able to base it upon indisputable facts.
But we, for our part, cannot stop at a cause and its immediate effect; for we know that this effect may in its turn become itself a cause. To judge of a measure, it is necessary that we should follow it from step to step, from result to result, until through the successive links of the chain of events we arrive at the final effect. We must, in short, reason.