In terms of something else

It can be difficult to perceive something new on its own terms.
The temptation is always to see it in terms of what you already know.
Yet, this approach closes your mind to the new.

Tai chi cannot be seen in terms of the conventional, external martial arts.
Yes, we require similar results:

1. Success in self defence
2. The ability to perform a variety of skills against a range of opponents
3. Appropriateness

But the means by which we accomplish and manifest these skills is quite different to mainstream combat systems.