by properties intrinsic in the stimulus but by meanings that the stimulus has acquired for the responding organism through experience—for example, Pavlow's dog's salivary glands responding to the sound of a bell. Third is the instrumental stage, as exemplified by a chimpanzee knocking down a banana with a stick. Here the response is determined by the intrinsic properties of the things involved (banana stick, chimpanzee's neurosensory-muscular system), but a new element has been introduced into behaviour, namely, the exercise of control by the reacting organism over things in the external world. And, finally, there is the symbol stage. In which the configuration of behaviour involves nonintrinsic meanings.
The first two stages exhibit a characteristic of the evolution of all living things: a movement in the direction of making life more secure and enduring. In the first stage the organism distinguishes between the beneficial, the injurious, and the neutral, but it must come into direct contact with the object or event in question to do so. In the second stage the organism may react at a distance, as it were—that is, through an intermediate stimulus. The conditioned reflex brings signs into the life process; one thing or event may serve as an indication of something else—food, danger, and so forth. And, since anything can serve as a sign of anything else(a green triangle can mean food, sex, or an electric shock to the laboratory rat), the reactions of the organism are emancipated from the limitations that stage one imposes upon living things, namely, the intrinsic properties of things. The possibility of obtaining life-sustaining things and of avoiding life-destroying things is thus much enhanced, and the security and continuity of life are correspondingly increased.
Which of the following is TRUE of the first stage of the evolution of mind?
A.The living things are unable to distinguish the beneficial, the injurious, and the neutral.
B.It is not necessary for a living thing to come into contact with another thing.
C.The intrinsic properties of things are the limitations imposed upon the organisms.
D.The first stage is characterized by the contraction of the pupil under increased stimulation by light.