The submissive obeys only because he chooses to...the slave obeys because he has to....
What i m seeing is that most of the people don t understands the difference between a sub person and one who needs to be a slave..so let's talk about this....
First of all...the submission to a dominant person is a need.
A slave is a person who submit himself totally to a dom.....he is a parasite...someone who is not able to rule alone his own life so chose to be a parasite to a host....he will do as is told and this is it....can t take decisions because he is not able...his goal in life is just to serve the dom as good as he can.....It s not important for him who is the person he serves as long as he can do it....he can change the host with no problems.
A sub.....well....the relation between a sub and his dom is a deep one....not random....the sub is the one who chose the dom or goddess because the submission part has to be a free will not a forced one..the relation is based on trust ,respect....continue with love-fear......can be even both in as the fear to lose the dom or goddess you love.....so its deeper and normally is long term even life time one.
A sub is a beta person...a beta person is a powerful person in real life who knows to rule his own life but needs the balance..so he submit just to one dom....and he chose it wisely.....because he has to trust and respect, cherish that person in all situations....its a symbiose relation...
A sub is the goddess lion......always near to protect her in need....this is the description I like to use...