when all the sense organs controlled and at the same time with mind and body are together it is also unity.

Question, how you can decide what is the real unity? Normally 'Unity is Unity' and it will be true on it own level but absolute unity when it true on the every level and condition and you have the peace without loosing our presence.

In general we are not connected with the our body, every moment mind is take bath in the sea of future or in the sea of past, but body anyway in the presence. That means body and mind have no connection. Energy flowing somewhere else then it's main track. When we bring both together, or I can say, when you learn to command on your mind, able to hold it(changing its direction or holding at one point by your own effort) then it can also called Yoga(Unity about yourself) because that time mind can be also in presence with the body. That will be the key to stop to being lost itself.

Other Unity, what can be more higher? It can be other possibility. One example, when you come out from your bodily level and analyse beyond body, then you can some other possibility to unify.

Now, I can say, when we connected with our sense organs and we unify itself with using sensual subject it is also unity but it is external unity, because in this unity you are using your sense organ, itself sense organ never complete and satisfy. You can think the unity through sense organs always incomplete. One example: when you listen some music and slowly you absorb that music because it is your favorite. Now same time if somebody call you with enough loud, but here you are connecting with your favorite music and cut off from the external world. Otherwise you could hear the other sound. Here, to get this condition like meditation you use your sense oragan(ears). Ears is the sense organ and this condition of the unity will be incomplete.

Same unity when get without engage sensual organ can more higher Yoga. So, Unity of the mind(in pure form, no effect of subject of sensual organs) and spirit is the real Unity.

Many peoples think, why they need to Unify, they are happy in the condition in which they are already but it is the same like one child think that he is right, Many time he cry and laugh through his victory on material things and losing material things. This all emotional transform is right but only on his level. It is not absolute right that is the cause why he sad and cry. When same child become elder then many changes take place in his thought but he could never understand this as he was child.

Same things is here. You cry and laugh and becomes happy on your victory for material object. weep to loose material object and promise to itself to not repeat this mistake again. You do same mistake again and again. For the moment you are happy but again sad. When you learn your mind and understand it you becomes more intellect and knowledgeable and then you think like the adult man as he was child before.

This is the need of peoples why the learn yoga or why they do yogic exercises and itself this is the definition of Yoga 'to attach with truth' , or unity of spirit and God, Unity of mind, body and spirit. (information based on Ish and Kath Upansishad)                                       ...Kashinath

According to Kathopnishad, After detachment of the subject, five Indria(sense) with Mana(mind) attach with pure spirit and intellect also act and destruct is the condition of great movent as called Yoga. Or in other hand, the condition of settled constant mind is Yoga..