Until we develop a workable system of thought communication with plants, we can never scientifically prove that plants are capable of psychological “affections” or emotions. Mental states are purely personal matters. We would never be sure that any other human being went through feelings of love, anger, hate and pity, similiar to our own, if he were not able to tell us of them. Until the plants can describe to us their inner emotions, we can never definitely know whether they have real feelings, and if they parallel the human variety in any degree. But just as we have become able to read a man’s mental processes by his facial expressions, tone of voice and bodily posture, so we can guess at plant emotion by external manifestations. When a flower greets the morning sun with expanded petals, uplifted head and a generally bright appearance, why should we not say it is happy and contented? When an approaching storm causes a plant to droop its body and contract its petals and leaves into the smallest compass possible, why is not fear, apprehension and melancholy indicated? When the jaws of the Venus Fly-Trap close on its hapless victim, they must do so with a savage joy akin to that of a Tiger springing on its prey. There are those who relegate a certain amount of intelligence to plants but deny them consciousness. They are unwilling to admit that plants are aware of their own physical and mental processes. This would seem to be the merest quibbling over terms and an entrance into that metaphysics which does away with all consciousness. If plants were not conscious, at least under stimulation, they would have long since perished from the earth through inability to react to new conditions. Francis Darwin says: “We must believe that in plants exists a faint copy of what we know as consciousness in ourselves.” Many scientists believe that life and consciousness always precede and are superior to organization. It is urged that possibly many plants possess consciousness without self-consciousness or introspection. After a thoughtful consideration of such facts as these, only the blindest prejudice can continue to laugh at plant intelligence. Why then has the world of human thought been so long and reluctant to acknowledge it? Simply because it always reasons along authentic and established lines. For many years it has been taught to associate animal movement with special groups of cells called muscles and intelligence with special groups of cells called nerve tissue. Failing to find any trace of nerve tissue in plants, it ignores a hundred convincing facts to the contrary, and declares that plant intelligence is a myth. Failing to detect a _mechanism_ of sensibility, it denies the existence of sensibility, even though in the little Mimosa the sense of touch travels from leaf to leaf before our eyes.