Didn't know majority of the forum is well in their 80s, watching the likes of Pele, etc.
With that logic nobody cant make a list then. Its not like there is a person in this world that has watched ALL the players in history, and also watched ALL the games they played. Even such a person could be wrong or biased towards a fellow contryman or whatever.
At the end of the day, making such a list depends entirely on a person's point of view and opinion on the subject. Ive watched pretty much every single game of, say, Victor Valdes, but have only watched about 1% of Buffon's games, and can still say with confidence that Buffon is a better goalkeeper.
Where i am going with this? Nowadays you have access to footage from pretty much every relevant football era. You can see highlights of Pele dribbling past entire professional teams and scoring beautiful goals, there's tons of footage of that. Couple that with facts and statistics, such as his goals scored, the world cup wins he has, and also add the opinion of other football greats that talk about him as if he was the greatest human that ever touched a ball, then you can make up a very valid opinion.
So if you have seen videos of Pele playing and scoring goals, and then you find out that he did that for nearly 10 years in a row in a consistent basis, how he was the main man in all the things he won, etc, then yeah you dont have to see every minute of his play to realize he's pretty much at the top.
Its either that, or whenever we make a list we will have to post our credentials on every single player, like:
1.- Messi (have watched all his games)
2.- Pele (just seen around half n hour of footage)
3.- Maradona (seen maybe two or three full matches and a bunch of youtube highlights)
4.- Cruyff (Same as above)
5.- CR7 (Have seen around 10% of the games hes played)
etc.
TL;DR: Nobody could ever make a perfect, unbiased list