I found the already existing bass tab as trascribed by Kieren Walters a
little bit difficult to follow if not perhaps inaccurate in parts.  Well
I didn't get the album out, but this is how I play it and I think it's a
little more straight forward and you ought to get some mileage out of
it.  I mean no offense Kieren, anyone who would take the time to
contribute to this cause is ok by me.
I Wish  by Stevie Wonder
Verse/Chorus
Ebm7     Ab7     Ebm7      Ab7     Ebm7     Ab7
g———————————————————————————————————————————————————
d————————————————————————5—6—8—6————————————————————  etc...
a———6———————————3—4—5—6———————————3—4—5—6———————————
e——————3—4—6—4—————————————————————————————3—4—6—4——
Bridge:
Bb7        C7      Fm7     Abm7    Bb7    C7       Fm7    Bb7+
g————————————————————————————————————————————————————————————————————
d—————————————————————————————————5—6—5—6—7———————————————————5—6—7—8
a———————————3—5————3—5—6—7—8—7—8——————————————3—5———3—5—6—7—8————————
e——3—4—5—6——————6———————————————————————————6—————6——————————————————
The Bb7+ is played like this:  (This is an augmented dominant 7th chord)
(meanining it has a sharp 5 and a flat 7)
(very hip)
e———x———————————
b———9——————————— pinky
g———9——————————— ring
d———8——————————— middle
a———x———————————
e———8——————————— first finger
The Abm7 in the bridge, I think is correct but I'm not really sure.
Transcribed by Jim O'Reilly
Happy Walkin' folks!