We can expect limited success in our endeavours to change but some change is better than none. We may be able to tip the balance in our favour.
What possible use is hindsight when the past is behind us and unchangeable?
Evil cannot exist without consciousness and free will.
Depression can only be defeated by science and rational enquiry not airy faerie emotional wallowing such as is to be found in most useless self help books.
Depression and determinism: can we influence our moods, can we “change our mind”?