A remark was made in a recent thread that "gullible" was not in the dictionary, which brought me to a full stop. Pulling down the appropriate volume of the Oxford English Dictionary, the entry for Gullible notes usage by the Scottish historian, Thomas Carlyle, in 1825, in his "Life of Schiller."
The entry does not say anything about the origin of the word, or where Carlyle obtained it.

GULLIBLE
Sung by Jillian Edwards

While it's fresh on my mind
As if it weren't all the time
Has it changed it all
Has it changed it all.

The song you sing
When you think of me
Is it soft and slow
Does it fly and land
Somewhere you want to go
Is it soft and slow
Does it fly and land
Somewhere you want to go.

I wish you were more convincing
Or I wish I were more gullible
Hope that there's no point that I am missing
Hope that it's not just too subtle.
(Repeat four lines)

And now I feel like a fool
For doing what you asked me to
And then you changed it all
So why'd you say
You miss my face
When you never show
Say you're gonna be there
But you never go
No, you never show
Say you're gonna be there
But you never go.

I wish you were more convincing,
etc.

And if it's a picture of me you need
Would you get to taking it
If it's heartache I need
Wuld you get to breaking it
And if it's a picture of me you need
Would you get to taking it
If it's heartache I need
Would you get to breaking it.

I wish you were more convincing
Or I wish I were more gullible
Is there a point that I'm missing
Or is it just too subtle
I wish you were more convincing
Or I wish I were more gullible
Is there a point that I'm missing
Or is it just too subtle.

(Confused?)

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