He therefore connected all, both animal and vegetable development, with intelligence, either spent and now unconscious, or still unspent and conscious; and in support of his view as regards vegetable life, he pointed to the way in which all plants have adapted themselves to their habitual environment.  Granting that vegetable intelligence at first sight appears to differ materially from animal, yet, he urged, it is like it in the one essential fact that though it has evidently busied itself about matters that are vital to the well-being of the organism that possesses it, it has never shown the slightest tendency to occupy itself with anything else.  This, he insisted, is as great a proof of intelligence as any living being can give.

“Plants,” said he, “show no sign of interesting themselves in human affairs.  We shall never get a rose to understand that five times seven are thirty-five, and there is no use in talking to an oak about fluctuations in the price of stocks.  Hence we say that the oak and the rose are unintelligent, and on finding that they do not understand our business conclude that they do not understand their own.  But what can a creature who talks in this way know about intelligence?  Which shows greater signs of intelligence?  He, or the rose and oak?

“And when we call plants stupid for not understanding our business, how capable do we show ourselves of understanding theirs?  Can we form even the faintest conception of the way in which a seed from a rose-tree turns earth, air, warmth and water into a rose full-blown?  Where does it get its colour from?  From the earth, air, &c.?  Yes—­but how?  Those petals of such ineffable texture—­that hue that outvies the cheek of a child—­that scent again?  Look at earth, air, and water—­these are all the raw material that the rose has got to work with; does it show any sign of want of intelligence in the alchemy with which it turns mud into rose-leaves?  What chemist can do anything comparable?  Why does no one try?  Simply because every one knows that no human intelligence is equal to the task.  We give it up.  It is the rose’s department; let the rose attend to it—­and be dubbed unintelligent because it baffles us by the miracles it works, and the unconcerned business-like way in which it works them.

“See what pains, again, plants take to protect themselves against their enemies.  They scratch, cut, sting, make bad smells, secrete the most dreadful poisons (which Heaven only knows how they contrive to make), cover their precious seeds with spines like those of a hedgehog, frighten insects with delicate nervous systems by assuming portentous shapes, hide themselves, grow in inaccessible places, and tell lies so plausibly as to deceive even their subtlest foes.