The phrase 'weak nature' is correct and usable in written English.
For example, you could use it in a sentence like, "His weak nature meant he was often taken advantage of."
I have no one to blame but myself and my weak nature.
"Given the weak nature of domestic demand now and going forward, it is likely that businesses will have increasing difficulty raising prices to consumers".
The cables noted the weak nature of Medvedev's electoral base, estimating he enjoyed the support of 20% of "urbanites" – voters in Moscow and St Petersburg.
The weak nature of tactile responses in hMT + (and their abolition by withdrawal of attention) suggests that hMT + may not serve as a supramodal motion processing module.
Due to the weak nature of intermolecular interactions in a molecular solid, the molecules retain their individuality making it possible to derive its properties from those of the molecular sub-units.
The subalpine Molasse is highly prone to such sliding activity given the dip of bedding, the surface topography and the weak nature of the marls that rapidly degrade when exposed to weathering.
But in town he regarded hospitality as a sign of weak natures.
Repentance is acknowledging our own sinful and weak natures, and hoping for His divine mercy.
We didn't allow the weaker nature to invade our minds".
That would have been a terrible mistake, a surrender to his weaker nature, he said.
This is probably due to the weaker nature of the non-covalent binding to the cell wall of the APF binding domain.
