"Sing a Simple Song" (Sly & The Family Stone)

Before Sylvester Stewart (a.k.a. Sly Stone) slipped into cocaine-fueled paranoia in the 70s, he made the tightest/loosest album of his career: Stand! (1969).  The three albums that precede it have some decent songs, but you can tell Stone was still trying to figure out the right blend of soul and psychedelic rock.  Not to mention the right balance of when to party and when to preach.
But Stand! fires on all cylinders.  There's catchy social commentary (the ubiquitous "Everyday People"), gospel-tinged motivational music ("I Want to Take You Higher"), and a lot of humor (the 13-minute "Sex Machine").
But the best song on the album in my opinion is "Sing a Simple Song."  From Freddie Stone's downright stanky guitar riff to Greg Errico's clockwork drumming (which has been sampled hundreds of times over), it encapsulates the whole Sly & The Family Stone sound in a little under 4:00.  Upbeat yet lowdown, churchy yet earthy, funny yet poignant, "Sing a Simple Song" is about trying to maintain perspective in an increasingly pessimistic, fast-moving world.  The thrifty lyrics also suggest that, when people put aside their problems and get back to basics, harmony is possible.
Although the sentiment borders on flower-power cheesiness, it's counterbalanced by The Family Stone's verse-trading delivery, which is sincere and true.  Plus, there's bassist Larry Graham singing do-re-mi-fa-so-la-ti-do in his deep baritone—a purposely jokey nod to the 1965 movie-musical The Sound of Music.
It's the kind of song that makes you feel good to your core.
It's also the kind of document that makes one wonder if the mad genius of 1971's There's A Riot Goin' On would have sounded radically different had Stone not slipped into addiction.

"Thank You For Talkin' to Me, Africa" (Sly & The Family Stone)

Most people are probably more familiar with the radio-friendly 1969 version of this track that appeared on Sly & The Family Stone's Greatest Hits (1970) album, where it was called "Thank You (Falletinme Be Mice Elf Agin)."  That version itself is a great song.  For one, it is the first real showcase of the incomparable Larry Graham's slap bass technique, which uses the slap of the thumb against the strings to mimic the sound of a kick drum and a finger pop to mimic a snare drum.  It also has some funky syncopated guitar interplay between Freddie and Sly Stone over Greg Errico's airtight drumming.
But nothing quite compares to the 7-minute version sitting sprawling at the end of There's A Riot Goin' On (1971)--an album that signaled the shift of Sly Stone's music away from the 1960s vibe of groovy togetherness to 1970s paranoia and gritty, drug-fueled decay.  There's A Riot Goin' On is essentially the soul/funk companion to The Rolling Stones' Let It Bleed and Sticky Fingers for slamming closed the coffin lid on the hippie dream.  It's an album that everyone should have in his/her collection: deeply funky, scary, gloomy, angry, funny, and innovative, all at the same time.  It's as much a tongue-in-cheek reply to Marvin Gaye's album What's Goin' On? as it is one frustrated artist's prophetic reply to Langston Hughes's poem "Harlem (Dream Deferred)."
The version on Riot is titled "Thank You For Talkin' to Me, Africa," and it has a very different groove from the original.  I've heard it described as a dirge--a funeral march, if you will.  But I wouldn't go that far.  I hear a slinky, confident, irreverent strut that thumbs its nose at pop charts, album sales, A&R people, and even Sly's own back catalog.
And it's Errico's in-the-pocket drumming and Graham's bass that anchors the whole thing--especially the bass.  Graham creates this hypnotic bassline with his slapping technique, and then every few bars, he sneaks in these raunchy little slides up and down the neck of his bass.  There is nothing funkier on tape.  Period.  Nothing the JB's, P-Funk, or Ohio Players ever recorded got this damn stanky.  This is/was the back door and the kitchen floor.