There is no Assertion but there is definitely Influence otherwise people like me wouldn't be here explaining to others how to make their lives better. :)

Assertion basically says that "it has to be this way for you whether you want it or not" while Influence says "this is how I would like it to be for you, if you have no objection".

Influence definitely works. The multi-billion dollar global industries of Advertising and Marketing are proof of that.

But you can be sure if any of the people involved in those mega-industries, with their unimaginably large resources, had ever really found a way to assert their messages instead of trying to influence with their messages, someone would have done it by now.

What happens metaphysically when you attempt to influence someone is that you force them to make a choice, even if it isn't a conscious one.

It doesn't matter what the influence is - it can be the influence of healing, the influence of advertising, the influence of trying to get them romantically involved with you (which has also become a multi-billion dollar industry now).

But this idea of forcing them to make a choice is what the outcome of your influence will be...the influence is yours, but the choice is theirs.

Notice that I've implied above that influence works if they have no objection.

Most people drift through their lives without any real sense of self-determination, purpose or direction. So if you offer them a choice that, in that moment, seems to them to be a better one than staying where they are, they would have no reason to resist.

The choices presented don't even have to positive ones. The negative "manipulation" of humanity is often driven by the choice of "if you don't do what we want you to do, something bad will happen"...but it's still a choice...even when it appears you have no other choice - but that's only when you manage to convince the population that they are only limited physical bodies trapped within a five-sense-based physical reality.

But try influencing someone to heal if they don't want to be healed, or try making them go on a date with you if they really don't want to, or try getting them to feel better if they really don't want to...in those cases, the differences between assertion and influence become very obvious.

From an even deeper perspective, we attract out of others (into our own reality) the behavior that is a vibrational match to our expectation of them - and the range of flexibility they have to offer in those behaviors is the range of our apparent influence over them.

So if someone is now behaving differently because of your changed expectation of them, it is because they had the flexibility within their multi-dimensional self to do that, and thereby engage with you in your reality through that different facet of themselves.

When you are out of range of what they have to offer, you simply cannot attract (or vibrationally match up with) any part of them in your reality any more and they effectively just vanish from your universe.

You are never changing anyone else. You are always changing your self. That's why the Law of Attraction is never the Law of Assertion.

If you change, and another person decides to change because you changed, it is because they are applying the Law of Attraction to themselves, not because you are applying the law of assertion to them.

If you change, but that other person decides not to change, it is not because the Law of Attraction is failing to work for you, but because that person is faithfully attracting that which they are most closely aligned with.

The Law of Attraction is not really about changing the universe and other people; rather it is about choosing what you wish to experience (and who you wish to experience it with) from the limitless possibilities of experience that are available to you.

As Eddie points out in his comment above, you can also choose a different perspective for your self. That shift in perspective will change the way you see other people, including your parasailing friend.