Final answer:
The text does not specify who first suggested the dictionary project to Samuel Johnson, but it began with a commission from a group of London booksellers in 1746.
Step-by-step explanation:
The individual who initially suggested the dictionary project to Samuel Johnson is not explicitly mentioned in the provided texts. However, the creation of Johnson's dictionary was a significant endeavor in the history of English lexicography, which began in 1746 when a group of London booksellers approached Johnson with the commission. This group perceived the need for a comprehensive dictionary of the English language and believed that Johnson was the ideal scholar to undertake this monumental task.