The big story in the cinephile world is obviously Sight & Sound magazine's once-a-decade poll on the greatest films of all time. Since everybody's critiquing it and making their own suggestions, I figured I'd share my own list, if I was ever so lucky as to be asked for it.
I am an inveterate list-maker, so what follows does reflect some serious thought and many changes and revisions. (I actually have a big list of greatest movies that I'm constantly updating--which is probably a weird thing to have, but if blogging has taught me anything, it's that I'm not alone in this practice.) However, I freely admit that the extent of my knowledge and experience in the world of cinema is limited, probably (hopefully!) more limited than anyone who actually participated in the poll, so I make no claim that my list is better than the poll's results, nor anyone else's personal list. There is, of course, no such thing as the "Greatest Movie Ever Made," so all lists such as this are merely games which help us discover/decide what aesthetic ideals we value.
My list has no overarching ideals to it except my own response to the movies themselves. I wouldn't describe the list as my "favorite" movies, because that word suggests to me those movies which I most enjoy watching again and again, but I have not tried to list those movies which are most "historically important" either. These films are those which have impressed me most strongly with their aesthetic brilliance and emotional power; they have left me in awe and altered the way I see the world. I present them here with no further detail or explanation; each film deserves volumes devoted to it, and I would need to write at least a post for every one or nothing at all, so I have opted for nothing at all.
So, as of September 2012, this is my list of the 10 Greatest Films of All Time:
1. Andrei Rublev (Andrei Tarkovsky, 1966)
2. Sunrise (F.W. Murnau, 1927)
3. Citizen Kane (Orson Welles, 1941)
4. M (Fritz Lang, 1931)
5. The Rules of the Game (Jean Renoir, 1939)
6. It's a Wonderful Life (Frank Capra, 1946)
7. On the Waterfront (Elia Kazan, 1954)
8. The Godfather: Part II (Francis Ford Coppola, 1974)
9. The Seventh Seal (Ingmar Bergman, 1957)
10. The Tree of Life (Terrence Malick, 2011)
OK, just two lines of explanation: If I had to justify with one film the ability of cinema to present beauty and humanity in the face of the vast wasteland of vulgar, obscene, and commercial junk that we are so often swamped with, I would choose Sunrise. If I had to justify film as an art form which can express the beauties and terrors of human existence on a level comparable to the other great arts--a film to mention in the same breath with Beethoven's Fifth Symphony, Hamlet, or the Sistine Chapel--I would choose Andrei Rublev.
And just because ten is too small a number, here are ten more films, in alphabetical order, which could on another day have made it into my Top 10:
2001: A Space Odyssey (Stanley Kubrick, 1968)
The General (Clyde Bruckman, Buster Keaton, 1926)
High Noon (Fred Zinneman, 1952)
Magnolia (Paul Thomas Anderson, 1999)
The Man Who Shot Liberty Valance (John Ford, 1962)
The Passion of Joan of Arc (Carl Theodor Dreyer, 1928)
The Red Shoes (Michael Powell, Emeric Pressburger, 1948)
The Seven Samurai (Akira Kurosawa, 1954)
Singin' in the Rain (Stanley Donen, Gene Kelly, 1952)
The Third Man (Carol Reed, 1949)
(actually posted April 2015)
