Sitting on a bar stool tells you that you want to look higher at this point. That you currently want to look over the situation, view and assess things differently. Another explanation is that the bar stool represents the way you are in life, or if this is balanced you can only answer yourself.
Yet another explanation is that you are currently relaxing, seeking peace and want to assess everything before continuing on your beaten path. The bar stool represents a new way of thinking but also instability and risk taking. Yet another explanation is that the bar stool you'd rather be lazy than tired; that you would rather be above everyone including yourself than to do something for it yourself.
The bar stool can be experienced both positively and negatively. As an alternative explanation, a Bar Stool can stand for like-minded searching, having the need not to be alone but to meet people. The Bar Stool ensures that you cannot ground, you cannot reach your base, as it were, you are not connected to your deepest self, you do not flow through and you do not want to find the connection and / or you do not bother.