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Of systems of equality. Wallace. Condorcet.

make any assertion whatever, and think it as unreasonable to be contradicted, in affirming that the moon will come in contact with the earth tomorrow, as in saying that the sun will rise at its appointed time.

With regard to the duration of human life there does not appear to have existed, from the earliest ages of the world to the present moment, the smallest permanent symptom or indication of increasing prolongation. The observable effects of climate, habit, diets and other causes, on length of life, have furnished the pretext for asserting its indefinite extension; and the sandy foundation on which the argument rests is, that because the limit of human life is undefined, because you cannot mark its precise term, and say so far exactly shall it go,

and no further, therefore its extent may increase for ever, and be properly termed indefinite or unlimited. But the fallacy and absurdity of this argument will sufficiently appear from a slight examination of what M. Condorcet calls the or. ganic perfectability or degeneration of the race of plants and animals, which, he says, may be regarded as one of the general laws of nature.

I have been told, that it is a maxim among some of the improvers of cattle that you may voli ii.

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Of systems of equality. Wallace. Condorcet.

breed to any degree of nicety you please ; and they found this maxim upon another, which is, that some of the offspring will possess the desirable qualities of the parents in a greater degree. In the famous Leicestershire breed of sheep, the object is to procure them with small heads and small legs. Proceeding upon these breeding maxims it is evident, that we might go on till the heads and legs were evanescent quantities; but this is so palpable an absurdity, that we may

be quite sure that the premises are not just, and that there really is a limit, though we cannot see it or say exactly where it is. In this case the point of the greatest degree of improvement, or the smallest size of the head and legs may be said to be undefined; but this is very different from unlimited, or from indefinite, in M. Condorcet's acceptation of the term. Though I may not be able in the present instance to mark the limit at which further improvement will stop, I can very easily mention a point at which it will not arrive. I should not scruple to assert, that were the breeding to continue for ever, the heads and legs of these sheep would never be so small as the head and legs of a rat.

It cannot be true therefore, that among animals

Of systems of equality. Wallace. Condorcet.

some of the offspring will possess the desirable qualities of the parents in a greater degree ; or that animals are indefinitely perfectible.

The progress of a wild plant to a beautiful garden flower is perhaps more marked and striking than any thing that takes place among animals; yet even here it would be the height of absurdity to assert, that the progress was unlimited or indefinite. One of the most obvious features of the improvement is the increase of size. The flower has

grown gradually larger by cultivation. If the progress were really unlimited it might be increased ad infinitum ; but this is so gross an absurdity that we may be quite sure, that among plants as well as among animals there is a limit to improvement, though we do not exactly know where it isą It is probable that the gardeners who contend for flower prizes have often applied stronger dressing without success. At the same time it would be highly presumptuous in any man to say, that he had seen the finest carnation or anemone that could ever be made to grow. He might however assert without the smallest chance of being contradicted by a future fact, that no carnation or anemone could ever by cultivation be increased to the size of a large cabbage; and yet there are assignable quantities greater than a cabbage. No man can

Of systems of equality. Wallace. Condorcet.

say that he has seen the largest ear of wheat, or the largest oak that could ever grow; but he might easily, and with perfect certainty, name a point of magnitude at which they would not arrive. In all these cases therefore, a careful distinction should be made between an unlimited progress and a progress where the limit is merely undefined.

It will be said perhaps, that the reason why plants and animals cannot increase indefinitely in size is, that they would fall by their own weight. I answer, how do we know this but from experience ? From experience of the degree of strength with which these bodies are formed. I know that a carnation long before it reached the size of a cabbage would not be supported by its stalk; but I only know this from my experience of the weak. ness and want of tenacity in the materials of a carnation stalk. There might be substances of the same size that would support as large a head as a cabbage.

The reasons of the mortality of plants are at present perfectly unknown to us.

No man can say why such a plant is annual, another biennial, and another endures for ages. The whole affair in all these cases, in piants, animals, and in the human ace, is an affair of experience; and I only conclude that a man is mortal, because the invari.

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Of systems of equality. Wallace. Condorcet.

able experience of all ages has proved the mortality of those materials of which this visible body is made,

“ What can we reason but from what we know ?" Sound philosophy will not authorise me to alter this opinion of the mortality of man on earth till it can be clearly pioved, that the human race has made, and is making, a decided progress towards an illimitable exteiat of life. And the chief reason why I adduced the two particular instances from animals and plants was to expose and illustrate, if I could, the fallacy of that argument which infers an unlimited progress, merely because some partial improvemen't has taken place, and that the limit of this improvement cannot be precisely ascertained.

The capacity of improvement in plants and animals, to a certa in degree, no person can possibly doubt. A clear and decided progress has already been made ; and yet I think it appears that it would be highly absurd to say that this progress has ne limits. In hui nan life, though there are great variations from different causes, it may be doubted whether since the world began any organic improvement whatever of the human frame can be clearly ascerta ined. The foundations therefore, on which the arguments for the organic perfectibility of man rest, are unusually weak, and can

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