Your child is in one of the most difficult stages filled with emotional meltdowns and temper fits, and as a result, despite his growing understanding of surroundings and self, he will often struggle with his reasoning skills. This might irk you quite a lot.
What you need to know
Children this age are very self-centred and focussed only on their needs. If they want something, they want it and no amount of reasoning can change that. If your child wants a banana and there is none at home, you can expect a huge meltdown and your child will not be willing to eat anything else. No amount of reasoning and pacifying will work and all you can do to pacify the child is to go to the market to get a banana.
Wired brains of little ones
These irrational, self-centred behaviours of children this age is due to fact that their brains are wired like this at this time. They are still in the early stages of cognitive development. Although they are making huge leaps in their thinking and imagination skills, they still lack the skills they would need to follow through their ideas. As a result they naturally feel anger, frustration and confusion. These are feelings they do not know how to handle and so tantrums are common.
Due to the nascent stage of cognitive development, it is very difficult to reason with your child. Children this age view everything in a simple way and often confuse fantasy with reality. Giving logical reasons is something the child is not able to comprehend yet and as the concept of time has still not developed, so waiting for something is not in their nature.