In science the credit goes to _ man who convinces the world, not to the man to whom the idea first occurs.

Explanation

The sentence should read:"In science, the credit goes to the man who convinces the world, not to the man to whom the idea first occurs."In this case, the word "man" is used in a general sense, referring to the person who convinces the world, without the need for an article ("a" or "the") before it. This is a more formal or philosophical way of expressing the idea.