[peritonlogon]

Hume thinks that
[ QUOTE ]

We form habits in our mind that constantly

[/ QUOTE ] ascribe [ QUOTE ]
cause and effect

[/ QUOTE ] to perceptions [ QUOTE ]
and for this reason, the relationship is

[/ QUOTE ] [ QUOTE ]
only a construct in our mind.

[/ QUOTE ]
Hume most certainly questioned cause and effect and determined that it was a human construct. As to whether or not he opined that the construct might be have a parallel in the phenomena, the hypothetical causes of our perceptions, he remained pretty silent.