We are ourselves the cause of our 
own conditioning.
We create our own states of mind.
We, alone, are responsible for our moods and emotions.
Some say the first noble truth is "Life is suffering" yet 
Buddha did not say this. Loosely he said that our cravings and aversions lead to 
suffering.
And... to add to the question of what the 
First Noble Truth is about.... within 
Buddhist terms...
The Ten Fetters of Existence
Self-delusion
Doubt
Clinging to Ritual
Sensuous Lust
Ill Will
Greed for Fine Material Existence
Greed for Immaterial Existence
Conceit
Restlessness
Ignorance
More on The four Noble Truths
Buddhism
Meditation