It is difficult to deal with such questions absolutely. Certainly Aristotle must be considered a scientist (one should also mention Archemides), but IMO the thrust of the question concerns post Renneissance. Also, some greatly regarded scientists are little known outside their fields, eg Guass, and some well known names, were more iconiclasts than good scientists, eg Galileo.
To synthesize it all, Newton is a good choice. True he coopted others ideas, or even their work, but he also went much further than anyone of his era, and also served as a great unifier of existing work, a la Euclid. Any discussion of physics, should begin with a recap of those that contributed new work in Gravity. The list is short: the Greeks, Newton, Einstein.
J
PS I think Tesla was both genius and madman. In the last 150 years, no one clearly stands above him. It is perhaps fitting that his name should so often be linked to a man he dispised, and from him he could not have ben more different: Thomas Edison.
