It has often been said that saying yes to something also means saying no to other things. That’s in the nature of saying yes. It’s a commitment to that ‘yes’ and the achievement it intends to represent.
Saying no to something doesn’t mean that you are also saying yes to something. There is no direct link between what you are saying no to and anything you could say yes to. It may not even be clear to you. You might not have found it yet. Saying no might be a process to finding what it is that you will say ‘yes’ to. However, there are too many options one can say no to, to reach a yes.
An interesting question may be: what is it that one might be avoiding by not choosing ‘yes’?
What does saying yes mean to you?
Could you see it as a decision that can’t be changed?
Is there an expectation that saying yes to something needs to lead to something that brings satisfaction?
Is there an assumption that what one says yes to needs to represent the right decision?
Is there a possibility that what you say yes to might not be welcome by someone important to you?

