All is in the title, again.
I know I have to say :
- This worker is efficient
- This reasoning is effective
But is it forbidden to exchange ?
- This worker is effective
- This reasoning is efficient
Is it allowed or completely false ?
What is the real difference ?
Here's the classic illustration of the difference between these two adjectives:
Imagine cleaning the floor with a toothbrush.
Is it effective? Yes, because it'll get your floor very clean.
Is it efficient? No, because it is a ridiculous waste of time and energy. It would be equally effective, but much more efficient, to do the job with a regular floor mop.
Effective means it is successful. So, a worker would be effective if they get the job done. They would be ineffective if they work hard all day but don't get the job done.
Efficient means fast, or not wasting time. So a worker would be efficient if they get the job done quickly. A worker would be innefficient if they have to waste time preparing their workspace.
Efficient can also mean not wasting other things. For example, a fuel efficient car goes a long way but doesn't use much fuel.