Van Halen on my mind today. Eddie should've been around and celebrating. In "Runaround," one of the lyrics most emphasized is "Oh what a fool believes." Sammy even sings it somewhat like Michael McDonald in the Doobie Brothers hit, but not so similar that a songwriting credit would have been owed. As far as I know, Michael created the "What a fool believes" expression. Maybe Sammy knew that Michael had co-written a Van Halen song ("I'll Wait") in the DLR days. Anybody have more info on how the line got in the song?
When you have a number one song that wins two grammys, the phrase that is your title becomes part of the culture.
If Michael McDonald was the first to use the line, then no, not pure coincidence, for Sammy must have heard the song. This is more about how conscious the use was. The theme of "Runaround" is like a sexual version of "What a Fool Believes." My current guess is that Sammy realized the similarity while he was writing the lyrics and then added "What a fool believes" and possibly later inserted "Oh" after Van Halen bandmates pointed out that Michael McDonald might otherwise demand a credit. Edit: there seemingly were no hard feelings between Hagar and McDonald a few years ago. Sammy Hagar Joins The Doobie Brothers And Fleetwood Mac For Isolation Performance | Society Of Rock I wonder if they were on friendly terms before "Runaround." Aha, I checked all the way back to Hagar in Montrose and yes that band and the Doobie Brothers did at least one show together, in 1975, making it possible the two men have known each other since the 70's. Given all that, I think the line was a nod or shout-out to Michael McDonald, maybe or maybe not approved by him prior to release.
Maybe by that point, McDonald figured it was ok for another artist to "Steal Away," if y'know what I mean.
Probably an influence from Ted Templeman. He produced the Doobies, McDonald solo, Van Halen and Van Hagar.
In the song Spindrift by Rush, Geddy sings the lyric “who cares what a fool believes”. Pretty sure Neil had heard that song before.
I hadn't heard of that Rush song. But that's a more significant change and as Rush by that point wasn't having hit songs, there would have been no point caring what Michael McDonald thought about it.
I think you validated there was something behind my suspicion. I doubt that Templeman suggested the line, but he might have been a go-between and reported that Michael McDonald didn't object. My hunch is that Sammy Hagar deliberately used it as a pre-chorus because it's a catchy proven winner and better than anything else he'd thought of. Sammy back then, unlike Neil Peart, was very much trying to write hits - I don't think he mindlessly used the line.