Are you humans irrational by nature?

Here's something to think about.
Rational behavior is flawed as it is coming from an irrational source.
Is there a way to be solely rational. To reject the irrationality of the human mind and act purely through logic?
I'll leave that up to you, I'd like to see what you come up with.

The underlying problem is that a human at some point must make an irrational assumption to be rational. For instance, we choose whether something is irrational based on ethical and moral axioms that were by the same standards "irrationally" assumed. Rationality could be in a seemingly paradoxical way considered an illusion that justifies (to yourself) our irrational nature through the contradiction of itself! (That one's quite hard to explain)
As another little challenge, I would love to hear an example that contradicts my previous statement.

Sorry can't brain today, I has the dumb.

I personally strongly believe that being fully rational is not desirable. Rationality is limiting, and one can achieve much more of one supplements reason with intuition and emotions and leaps of faith. I think there is a danger of becoming a sociopath if one is too focused on rationality without emotional and moral counterbalance (love and remorse are not always rational, and yet they improve the humans reactions). Logic is too limited a tool to use it exclusively in my opinion. Now logic is wonderful as one of several tools in our toolbox to use in conjunction with others to arrive at a decision.

imagination is built upon irrationality

Sure you can be solely rational. That eliminates anything novel, new, or original. Being completely logical would necessarily need to adhere to set perimeters much like a computer. As long as you don't imagine any new possibilities, you can certainly be rational.

Logic is a language developed from humanity's perception of reality to map out said perception and turn randomness into dependable concepts. These concepts, once separated from their experience, do not exist in the world. They are nodes and archetypes developed over our entire history of paying close attention to perception's patterns.

Logic was only ever developed for making decisions. One used logic to develop a dependable understanding of what was going on beyond their perception. Back in the day, we used superstition, throwing bones on the ground to weigh our actions against the uncertainty of the future. As time went on, we developed knowledge, wisdom, experimentation, and logic. All this continues merely to exist to aid our actions, and not to define reality. Reality, whether rational or not, has always existed as something beyond humanity's perception of reality. It is irrelevant that rationality ultimately evolved out of the irrational. I'd still make my decisions based on logic, whenever possible.

TLDR: Remember that part of Watchmen when Dr Manhattan decides to save the earth because he finds out his girlfriend resulted from a rape? It's something like that.

I personally believe that we should all strive to be as rational as possible. Being irrational only brings problems, while being rational can help you solve any problem. I don't think being logical has any of those downsides people mentioned. We really shouldn't let our emotions control us but should let rational logic guide everything in our life. Being rational doesn't mean being emotionless, it means understanding your emotions.

Doing something because it makes you happy is a rational thing to do. You can experience all emotions without acting on the impulses that will get you into trouble. I think humans are irrational at times, normally when we are rushed. If you can calm yourself down and think things through, I think everyone can be logical and rational however.

Humans are animals. While we have evolved and developed logic and reasoning, we still have our impulses and instincts. That said, such impulses and instincts should be saved for when logic and reasoning are not suitable, such as during emergencies or when a quick impulse decision is needed; or when a solution is beyond one's logical abilities.