The short answer is yes and no. From the wiki:

Reincarnation is the religious or philosophical concept that the soul or spirit, after biological death, begins a new life in a new body that may be human, animal or spiritual depending on the moral quality of the previous life’s actions.

No, I do not believe in that. I don’t believe in reincarnation, or anything else for that matter, in a dogmatic way. I think it’s quite silly that, when people can “see” their past lives, they’re usually some celebrity like Henry the VIII or Joan of Arc. Mathematically, the odds of being someone famous in a past life are infinitesimally high. There was only one Joan and one Henry, whereas there were billions of peasants.

As usual, when it comes to all of life’s big questions, I turn to science. I believe in science. Science is awesome! Science tells us that there are electrical impulses in our brains that make up our actions, beliefs, personalities and what we see, hear or like to eat. We each have our own gray matter that tells us who we are and what we think about things. I’m using mine now to type this sentence. The brain and its electrical-ness is what makes you different from me, which is awfully neat, don’t you think?

In fact, our brains reincarnate all the time, so to speak. It’s called transduction, which is the conversion of a stimulus from one form to another. For example, we see things through a process called phototransduction, in which elementary particles of light are converted into electrical signals in our brains. Light particles cause a change in a protein called rhodopsin, which through a few magical steps, transforms into electrical impulses. It’s all very bookish, but here’s a chart:

I believe in the kind of reincarnation that transforms tiny light particles into electrical impulses in my brain. Ta-dah! 

Our brains comprise the sum of humanity’s knowledge, kindness, humor, understanding and love. They also contain all of our hate, discouragement and fear. They are what we make of them. Without our big primate brains, we wouldn’t have been able to come up with a concept like reincarnation in the first place. The electrical impulses and synapses in my brain are different from yours, which is what makes us unique, but it’s our brains in general that make us all the same. All humans have one and they operate in generally the same way.

But do I believe that whole, discrete people– or ghosts–are floating around in the sky just waiting around for another body to jump into? No. Once the light goes out, it’s gone. Energy can’t float around as a formerly-human entity haunting the living and going WOOOoooOOOOooo.

However, that energy isn’t lost. The First Law of Thermodynamics states that energy can be changed from one form to another, but it cannot be created or destroyed. The Second Law of Thermodynamics: in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state, a.k.a. entropy. In other words, energy goes from a usable form to a less usable form.

Based on physics logic then (my favorite kind of logic), the energy that makes up a human cannot be transferred in full to make another human, but it might become part of another human, or it might become something else like a rainstorm or a wave or a cloud. In any event, the energy that makes up you and me cannot be destroyed; it will just change forms.

When I die, my body will finish the process it started when I was born of turning into the same decaying matter as everything else. If I am not cremated, my body will become host to an entire civilization of critters whose job it is to disassemble me. Even if I am cremated and spread over some land somewhere, some part of me might be ingested by a worm that will be eaten by a bird which will then fly through the sky with me in its belly. I’ll be pooped out onto someone’s windshield only to start all over again as something else.

If I am really lucky, I will live on in people’s memories and maybe some of my words will remain to be transformed from tiny light particles into electrical impulses. And I am totally fine with that.