Here and there I've seen polls asking people to compare these 2.
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Philip Seymour Hoffman:
Is it possible to say?
Philip Seymour Hoffman has 1 disadvantage: his physical appearance. I don't mean actors have to be, or should be, good-looking. But his looks are a hindrance in that he can't play convincingly a character that is truly good or truly bad. His characters usually aren't really evil, brutal or cruel- they're just effeminate or weak or cowardly or creepy or perverted or nasty or cocky or awkward or flamboyant or desperately lonely or pathetic or..., in short, unpleasant, detestable and pathetic. Philip Seymour Hoffman, in my opinion, is braver. He takes unpleasant roles many people would say no to, he plays them fearlessly, honestly, creatively. "Capote" is 1 of the few films in which he's a leading actor, the name Philip Seymour Hoffman understandably often comes 2nd or 3rd or 4th or even later in the cast. It doesn't matter. Among actors who often play supporting roles, he stands out as the finest, or 1 of the finest at least. A very talented and versatile actor, who shows that many people have put too much focus on physical transformations (like getting super fat or super thin) without realising that the more important transformations take place on the inside, since he has played various different roles without changing much in his weight.
This video shows very well his courage and versatility: http://www.youtube.com/watch?v=hXAeLWn5AYQ
I, however, can't imagine him in any of Daniel's roles.
On the other hand, I can't imagine Daniel in any of Philip's roles, either. I have seen him playing a gay character. I have seen him being cold-hearted, greedy, misanthropic, cruel, hateful, racist... I have seen him being stiff, pompous... But effeminate, weak, cowardly, nasty, pathetic? Daniel's talent is not to be doubted. He doesn't give the impression that he's acting- he transforms into the character. As I've said, I still once in a while find it difficult to believe it's really him in "There will be blood" and "Gangs of NY". But while he's incredibly talented, I think his physical appearance is an obstacle if he's supposed to play Philip Seymour Hoffman's roles.
If asked to choose between these 2 brilliant, extraordinary actors, I still go for Daniel Day-Lewis. Not because of his offscreen qualities, but rather, the fact that, it's Daniel who made me realise what an actor can do, and totally changed my view on acting. He becomes the characters, plays such a wide range of characters so that no 2 performances are the same and at the same time, also impresses me, overwhelms me, strikes me in the head and touches me deeply. Philip Seymour Hoffman doesn't do so, though he's truly talented, 1 of the best in the US. I mean, he always gives a good performance, whenever I see his name I can expect him to be very good, but he's always good and at the same time his performances don't really hit me and overwhelm me the same way, I can't really pick a single outstanding, incredible role. The same goes for Meryl Streep. (That's why in some sense it's better to say Meryl Streep's male counterpart is Philip Seymour Hoffman, whereas Daniel Day-Lewis pretty much stands on his own).