Chapter XXVII

. On Instinct And Mechanical Tendency.

It is as if nature had wished, in the mechanical tendencies of animals, to give the investigator an illustrative commentary upon her works, according to final causes and the admirable design of her organised productions which is thereby introduced. For these mechanical tendencies show most clearly that creatures can work with the greatest decision and definiteness towards an end which they do not know, nay, of which they have no idea. Such, for instance, is the bird’s nest, the spider’s web, the ant‐lion’s pitfall, the ingenious bee‐hive, the marvellous termite dwelling, &c., at least for those individual animals that carry them out for the first time; for neither the form of the perfected work nor the use of it can be known to them. Precisely so, however, does _organising_ nature work; and therefore in the preceding