Who are the most recognizable scientists?

Chad Orzel posts in his blog about

This raises the question, though, of who belongs on the Mount Rushmore of Science: Who are the four most iconic scientists out there, who deserve to be memorialized in titanic stone sculptures, ideally on the Moon or somewhere similarly cool?

Iconic: see semiotic and Semiotics for Beginners

Icon/iconic: a mode in which the signifier is perceived as resembling or imitating the signified (recognizably looking, sounding, feeling, tasting or smelling like it) - being similar in possessing some of its qualities: e.g. a portrait, a cartoon, a scale-model, onomatopoeia, metaphors, 'realistic' sounds in 'programme music', sound effects in radio drama, a dubbed film soundtrack, imitative gestures;

Well, since their features are to be carved, an average 'man' must be able to identify them(the carvings) as being similarities of them(the scientists under question).

But as "art imitates art", there must already be some depictions of those scientists that are deeply engraved in people's minds for the project to serve its purpose. Otherwise one would creating those images now: not a bad idea, actually, but does not serve the purpose(there is no face that is iconic).

Einstein - yes , most certainly yes. Almost everyone has seen that one depiction of him.

Archimedes - there is a bust that is believed to represent him, but by now, it looks like a generic Greek (similar to what Julian Barnes writes about that painting the raft of medusa). Not a candidate.

Newton: hmm, we only have a dim idea of what he might have looked like (assuming you have not seen that history channel program on newton where they have actually had some actors act like newton (who knows how he 'acted'!)).

Darwin: yes - many people remember that beard-y picture in a nice angle(only, the cited article does not have the one I have in mind).

Freud : yes this photo is recognizable (not that I think he was a great scientist or anything).

Marie Curie : yes everyone knows her by face.

Faraday: may be. He and Marie Curie have beeen on currency notes already - which is one way by which many people might know their faces (but also, lets not forget that currency notes are long gone now and so are the people who used to trade with them).
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