Reasoning in the chimpanzee: I. Analogical reasoning.

Analogical reasoning in a 16-yr-old female chimpan7.ee (Sarah) was studied in five experiments. The general design of the analogy problems was where same was Sarahs plastic symbol for same. Sarah solved analogy problems with two types of displays: (a) forced choice, in which she had to com-plete an analogy by choosing the correct B from a set of alternatives (Experi-ments I A, In, and 3A) and (b) same-different, in which she had to complete an analogy by choosing the correct predicate, Same or Different (Experiments 2 and JB). In addition, she correctly solved both figural analogy problems, in which the stimuli were geometric figures and the relations among them were differences in size, color, or marking (Experiments I A, I n, and 2), and concep-tual analogy problems, in which the stimuli were household objects and the relations were functional and spatial (Experiments 3A and 3n). Simple mecha-nisms for problem solution, e.g., physical matching, feature combination, and choice on the basis of association, were ruled out. The data strongly indicate that Sarah used the relation between A and A to solve the analogy problems (Experiment IB). The implications for theories of human and animal cognition are discussed. Are there cognitive abilities that are and for Thorndike, reasoning was the pi i i unique to humans? Most influential nineteenth pal cognitive difference between hum century theorists proposed that reasoning and nonhumans. In contrast, a few e; was restricted to humans (e.g., Hohhouse, theorists suggested that nonhumun anin