Evolution Thus Is Merely Contingent On Certain

The History Of Science Knows Scores Of Instances Where An Investigator Was In The Possession Of All The Important Facts For A New Theory But Simply Failed To Ask The Right Questions.

New Gene Pools Are Generated In Every Generation, And Evolution Takes Place Because The Successful Individuals Produced By These Gene Pools Give Rise To The Next Generation.

To Take An Unequivocal Stand, It Seems To Me, Is Of Greater Heuristic Value And Far More Likely To Stimulate Constructive Criticism Than To Evade The Issue.

A New Species Develops If A Population Which Has Become Geographically Isolated From Its Parental Species Acquires During This Period Of Isolation Characters Which Promote Or Guarantee Reproductive Isolation When The External Barriers Break Down.

All Interpretations Made By A Scientist Are Hypotheses, And All Hypotheses Are Tentative. They Must Forever Be Tested And They Must Be Revised If Found To Be Unsatisfactory. Hence, A Change Of Mind In A Scientist, And Particularly In A Great Scientist, Is Not Only Not A Sign Of Weakness But Rather Evidence For Continuing Attention To The Respective Problem And An Ability To Test The Hypothesis Again And Again.