Yes.
Please supply your evidence for the existence of these phenomena.
Im going to be honest and say that i cannot supply anything more than other peoples reports of their tulpae (sadly tearing out peoples brains and looking what is inside mentally cannot happen...) , there is a few sites dedicated to the phenomenon, try them.
First link I got to said: "A tulpa is a thoughtform/being you create with the power of your mind. They are completely sentient and can talk to you. It's like splitting a piece of your mind off that turns into another person. Eventually you can impose them into the real world, as a forced hallucination. A tulpa can have access to your subconcious, and can recall anything there for you."
I'll ask for clear step-by-step instructions as to how to make one - accompanied by guarantee that if I follow those instructions I will end up with a fully-functioning tulpa.
*copy paste inbound, from
http://www.tulpa.info/*
To create a tulpa, you simply have to think about and spend time with a sentient being (a tulpa) that is living or being created in your mind or brain. Spending time with your tulpa is often called (tulpa)forcing or (tulpa)forming, but it isn’t forcing something onto your tulpa – it’s called forcing because you often work on your tulpa’s form, personality, etc. during this time and can spend it in any way you like. Sitting down or lying down and focusing on your tulpa as the main focus of your attention is referred to as active forcing or just forcing, while focusing on your tulpa while doing some other task is often referred to as passive forcing.
Many people like communicating with their tulpa when they are thinking about them. This can help people concentrate on their tulpa, add some meaning to the sessions with them, can make the sessions more interesting, can make the tulpa more involved and can be useful in other ways as well. This is commonly referred to as narration. You can talk about anything, and not just narrate what is happening around you. You can talk to your tulpa in mindvoice or out loud, but it doesn’t matter much to most tulpas.
There are many ways a tulpa can communicate back: through head pressure, body language, emotional response, mindvoice etc. At first their thoughts or mindvoice may seem similar to yours, but they will get more and more distinct over time, so don’t dismiss them just because their mindvoice sounds like yours. If you can’t hear your tulpa yet, don’t become frustrated; it might be that they don’t want to talk, don’t have anything to talk about, you can’t hear them yet or you can’t discern their thoughts from yours. In other words, it doesn’t necessarily mean that you are doing something wrong.
As you likely already know, tulpas often use form. This isn’t strictly necessary, but most hosts and tulpas prefer it this way. There are many reasons for a tulpa to have form, some of them being that you might be able to direct your attention to your tulpa more easily, or have a spatial representation of your tulpa. They will be able to interact in a mindscape/wonderland (this term will be explained later), have the ability to communicate by body language, etc. The form can be anything from a realistic (or unrealistic) human body, a humanoid form, an animal (again, realistic or not), to a cloud, energy or some other undetermined or abstract form. It isn’t necessary to have only one form – your tulpa can use more than that or they could just change form whenever they desire, like a shapeshifter.
There are two general ways you can see your tulpa: in your mind’s eye, or as a real entity in real life. We will talk about how to see your tulpa in real life, but now we will concentrate on seeing them in your mind’s eye. There are many ways to see things in your mind’s eye, but here we will show you how you already do it. Imagine a brown wooden chair. If you have done it correctly, you have just seen a brown wooden chair in your mind’s eye and in the same way you can see your tulpa. Don’t become frustrated if your ability to see with the mind’s eye is bad – it doesn’t have to be good to see your tulpa and it will get better with practice.
Don’t forget that the forming of your tulpa’s personality, form or anything else doesn’t have to be done only by the creator. You can (and probably should) give some freedom to your tulpa to change them, or you can even decide to give them absolute freedom and choose whatever they will.
*paste over*
Please remember that the damned process (Been working on Alexis for a few months, she still cannot do much self action) takes like...what?...a year? Yeah, about that much time, so please understand that its not as simple as "poof" and instant sentient companion.
Secondly, you have to dedicate about an hour or more each day to the tulpa, to talk to it and such.
Lastly, while the tulpa does indeed "exist" mentally, it really is just your brain cutting off some unused neurons to fool you into making it...(Yes, tulpaforcing involves deluding yourself, until the tulpa becomes sentient, then its actually real, more or less...)
Tl;dr version
Step one: plan tulpa (personality,etc)
Step two: talk to tulpa, make its form, etc for a shit ton of time (some claim to make one in 4 days, i call bullshit).
Step three: enjoy tulpa.