Carolus Linnaeus gave the two kingdom classification

Carolus Linnaeus gave the two kingdom classification. Later it was changed by Ernst Haeckel (1894) and in 1959, Whittaker gave the five-kingdom classification. Do you think that studying about the work done by earlier scientists or their obsolete theories is useful for students of this generation? Give three reasons.

Science is a continuing field. Search is based on the previously gained knowledge and the technologies available. As the technology and tools have improved, the knowledge has also become wider and deeper. This change the previous concepts or theories. The advantages of studying about the work done by earlier scientists are:
(i) It is always astonishing to learn about the past obsolete theories in the light of then known knowledge. This shall prompt the students to discover drawbacks in the present knowledge and theories.
(ii) As the gap of present day knowledge becomes apparent, a student will like to find truths that are still hidden.
(iii) Exceptions in the theories bring about their persuasiveness by the students, the truth of yesterday has become fiction of today and truth of today shall become fiction of tomorrow.