Many people I know think they are smart and yes they are in relative terms i.e. when measured against their partner or colleague or even family member. However, in an absolute sense, we are all ignorant as it is not possible to know everything so we must always try to be humble about what we do not know and know it might affect what we think we know.
Humans have developed a measure of the relative intelligence the form of an IQ test. Despite much of the current media tripe about IQ not been a fair indicator or intelliegence is it the best measure we have at the moment and it has proven to be a good measure of ability and potential.
Now, the question comes, can you increase your measure of ability and potential? My view is that the answer is yes and it is the principle behind the Matthew Effect.
How we increase our intelligence is by reading, in particular, it must be text i.e. books. These reason for this is it developed our neural network within the brain i.e. exercises it. The brain gets stronger and enjoys reading more and the feedback loop increases to such an extent that intelligence grows.
Keep reading the text, you will get smarter and become more in control of your life and enjoy it more.
I am not a religious person but Matthew 13:12 hit the nail on the head:
*New International Version*
Whoever has will be given more, and they will have an abundance.
Whoever does not have, even what they have will be taken from them.
*New Living Translation*
To those who listen to my teaching, more understanding will be given,
and they will have an abundance of knowledge. But for those who are not listening,
even what little understanding they have will be taken away from them.
*English Standard Version*
For to the one who has, more will be given, and he will have an abundance,
but from the one who has not, even what he has will be taken away.
Effectively this means we you need to know what you need to learn. Smart people adapt to change because they see it coming the less smart don't so they die off or have a very difficult life. Get smart you can do it, the only thing holding you back you.