John Perry Barlow, poet, activist and longtime lyricist for the Grateful Dead, has passed away at the age of 70. The news was confirmed by the Electronic Frontier Foundation, which Barlow founded in 1990.

“With a broken heart I have to announce that EFF’s founder, visionary, and our ongoing inspiration, John Perry Barlow, passed away quietly in his sleep this morning,” EFF’s statement reads. “We will miss Barlow and his wisdom for decades to come.”

Barlow was born in 1947 in Wyoming and met and became friends with Bob Weir in high school in Colorado. Starting in the early ’70s, Barlow became the primary lyricist and co-songwriter for Weir’s contributions to the Dead catalog, eventually amassing a collection of songs that included “Mexicali Blues,” “Cassidy,” “Estimated Prophet,” “The Music Never Stopped,” “Hell in a Bucket,” “I Need A Miracle,” “Black-Throated Wind” and “Throwing Stones,” among others.

Barlow and Weir’s lifelong friendship also included spending time on Barlow’s Wyoming ranch, which helped to inspire Weir’s so-called “cowboy songs” and the tracks on his recent solo album Blue Mountain. Barlow also worked with Dead keyboardists Brent Mydland and Vince Welnick and others, later writing lyrics for The String Cheese Incident’s Michael Kang.

Barlow was also an avid activist for Internet freedom. As EFF writes in their statement following his death, “It is no exaggeration to say that major parts of the Internet we all know and love today exist and thrive because of Barlow’s vision and leadership. He always saw the Internet as a fundamental place of freedom, where voices long silenced can find an audience and people can connect with others regardless of physical distance.”

Barlow had suffered through poor health in the past few years, including a heart attack in 2015, and was unable to attend the Dead’s Fare Thee Well concerts that year. Multiple benefit concerts were held in his name to raise money for his medical costs, featuring musicians like Weir and others in the greater Dead and Bay Area communities.

Below, watch a video of the Grateful Dead playing “The Music Never Stopped” at New Jersey’s Capitol Theatre in 1977.