The rock world -- and the world in general -- was stunned when it was announced on Friday (January 10th) that Rush drummer Neil Peart had lost a three-and-a-half year battle with brain cancer three days earlier on January 7th. The 67-year-old Canadian drummer, lyricist and author passed away in Santa Monica, California, just four-and-a-half years after he and Rush retired from the stage.

The surviving members of Rush, bassist/singer Geddy Lee and guitarist Alex Lifeson, issued a statement on Friday in which they said their "friend, soul brother and bandmate of 45 years" was "incredibly brave" in the fight against his illness. Not too long after, an immense outpouring of grief-stricken tributes began from both fellow musicians and fans, for whom Peart was a lasting and monumental inspiration.

Foo Fighters main man and Nirvana drummer Dave Grohl, who inducted Rush into the Rock and Roll Hall of Fame in 2013 and cited Peart as the reason he began playing drum, issued a statement saying, "Today, the world lost a true giant in the history of rock & roll. An inspiration to millions with an unmistakable sound who spawned generations of musicians (like myself) to pick up two sticks and chase a dream. A kind, thoughtful, brilliant man who ruled our radios and turntables not only with his drumming, but also his beautiful words."

Grohl added, "Thank you, Neil, for making our lives a better place with your music. You will be forever remembered and sorely missed by all of us. And my heartfelt condolences to the Rush family."

Foos drummer Taylor Hawkins said simply, "Neil Peart had the hands of God. End of story."

Metallica drummer Lars Ulrich wrote on Instagram, "Thank you Neil. Thank you for inspiring me and for all your help and advice along the way, especially in the early days when you took the time to talk to a young green Danish drummer about recording, gear and the possibilities that lay ahead... Thank you for what you did for drummers all over the world with your passion, your approach, your principles and your unwavering commitment to the instrument! Rest In Peace."

Mike Portnoy, the co-founding former drummer of Dream Theater reveled that he was among the few that was aware of Neil Peart's cancer diagnosis: "Being part of the inner-circle, I've been aware for, about, the last two years, or so. And, y'know, obviously, I haven't talked about it, and y'know, respected his privacy and his family's privacy. So, even though I knew this could possibly be an inevitability for the past couple of years, it's still shocking now that it's actually here. It's just, you never imagined a world without Neil, Geddy, and Alex all walking along it, y'know?"

Portnoy, who revered him as a drummer, told us that one cannot overstate the range of Neil Peart's talents: "I mean, the fact that he was the band's lyricist and wrote such intelligent poetic lyrics -- it was a huge, huge influence, as well -- as well as the books he's written over the past 20 years or so. After the horrible tragedy of losing his first wife and daughter, he wrote the Ghost Rider (Travels On The Healing Road) book, which is one of the most inspirational books I've ever read in my life."

Triumph drummer Gil Moore, a fellow Canadian who made his bones on the North American concert circuit the same time as Rush, explained how Neil Peart carried on the tradition of aggressive lead drumming, which he learned from his heroes: "When I think of Neil's playing style, the first guy I think of is Ginger Baker, Keith Moon, Mitch Mitchell. Neil's style, which is, sort of, a very drummer take all -- he plays the heck out of everything on his drums, right? So, opposed, to say, the guys that evolved from the Alan Jackson, Levon Helm, John Bonham-school and, kind of, lay back between the waits on these spaces; the Keith Moon's and the Neil Peart's, and the Ginger Baker's, and the Mitch Mitchell's -- they were the guys that went the reverse route, and they filled all over the place, and kind of, drove the rhythm from in font of it, rather than sitting behind it."

Judas Priest drummer Scott Travis was an instant fan of Neil Peart, and actually met him as a teenager before a gig on Rush's tour behind 1978's Hemispheres: "I didn't know the man -- I obviously knew him as a phenomenal drummer and songwriter and everything else, but I actually respected the fact that he was, kind of, invisible and he wanted his personal life to stay separate from his music life. 'Cause, as we know nowadays everybody wants everything about them to be known, and documented and filmed -- and he, of course, was the antithesis of that. So, I respected that a lot about him. This was, of course, long after he had influenced me as a drummer and just changed my world, as far as drumming."

Kenny Aronoff, best known for his years drumming for John Fogerty and John Mellencamp, told us that news of Neil Peart's death transcended the music community: "You never know how people will react to somebody dying until they die. With Neil, it didn't surprise me, but Neil passing really affected drummers and the music industry and people in general. My brother's a psychoanalyst and he knew who Neil Peart and Rush was and felt bad. I mean, Neil's passing affected so many different types of people in and out of the music business. It didn't surprise me -- but, pretty amazing."

Canadian prime minister Justin Trudeau wrote, "We've lost a legend. But his influence and legacy will live on forever in the hearts of music lovers in Canada and around the world. RIP Neil Peart."

Tool paid tribute to Peart during the band's concert Friday night (January 10th) in San Diego, California. During Danny Carey's drum solo, a photo of Danny and Peart was projected on a massive screen behind the stage. Tool also played a partial cover of Rush's "A Passage To Bangkok" in tribute to Peart, whose death was announced earlier in the day and who was a huge inspiration for Carey.

Other rock artists posted tributes or condolences on social media:

Paul Stanley: "Absolutely Horrible News. Neal Peart has died after fighting brain cancer for years. His later life was filled with so much family tragedy. So, so sad. I'm just shocked."

Flea: "I'm gonna go spend the day air drumming. R.I.P. Neil Peart. That dude f**king shredded."

Gene Simmons: "Neil was a kind soul."

William Corgan: "There isn't a modern rock drummer alive who hasn't heard him, and spoken his name with a reverence that's reserved for the very few."

Nickelback: "His impact on rock history is indelible and his influence on drummers everywhere inescapable."

Weezer's Patrick Wilson: "His dedication and RE-dedication to his craft is a lesson in always improving."

Brian Wilson: "Neil was one of the great drummers and he'll be missed."

Judas Priest: "Neil's legendary drum work and inimitable style will always resound in rock n roll."

Tony Iommi: "We've lost another one of the greats."

Tom Hamilton: "He was an amazing drummer and made a huge contribution to Rock music."

Josh Freese: "A true artist and a sweet, good guy. And probably the most air drummed drummer of all time."

Charlie Benante: "There are drummers and then there is Neil Peart."

Bill Ward: "What is left is a life's work to praise, converse about, to be in awe of, knowing the world is a better place for your triumphs."